Apparatus and method for acquisition of on-demand system information in connected state

ABSTRACT

A wireless terminal that communicates over a radio interface with a radio access node of a radio access network (RAN). The wireless terminal comprises receiver circuitry, transmitter circuitry, and processor circuitry. The receiver circuitry is configured to receive, in a radio resource control (RRC) connected state, one or more configuration messages via dedicated signaling(s). The one or more configuration messages may comprise a timer configuration for a timer and a configuration for Physical Downlink Control Channel (PDCCH) monitoring. The transmitter circuitry is configured to transmit, in the RRC connected state, a system information (SI) request message to request at least one system information block (SIB). The processor circuitry is configured to start the timer based on the timer configuration and to perform an SI acquisition process. In an example embodiment and mode, the SI acquisition process comprises reception of Downlink Control Information (DCI) on PDCCH based on the configuration for PDCCH monitoring, and reception of Physical Downlink Shared Channel (PDSCH) scheduled by using the DCI. The SI acquisition process continues until the at least one SIB is successfully received or until the timer expires. Methods for operating such wireless terminal and the access node are also provided.

CROSS REFERENCE

This Nonprovisional application claims priority under 35 U.S.C. § 119 onprovisional Application No. 62/886,042 on Aug. 13 2019, the entirecontents of which are hereby incorporated by reference.

TECHNICAL FIELD

The technology relates to wireless communications, and particularly tomethods, apparatus, and techniques for requesting, transmitting,updating, and using system information (SI) in wireless communications.

BACKGROUND ART

In wireless communication systems, a radio access network generallycomprises one or more access nodes (such as a base station) whichcommunicate on radio channels over a radio or air interface with pluralwireless terminals. In some technologies such a wireless terminal isalso called a User Equipment (UE). A group known as the 3rd GenerationPartnership Project (“3GPP”) has undertaken to define globallyapplicable technical specifications and technical reports for presentand future generation wireless communication systems. The 3GPP Long TermEvolution (“LTE”) and 3GPP LTE Advanced (LTE-A) are projects to improvean earlier Universal Mobile Telecommunications System (“UMTS”) mobilephone or device standard in a manner to cope with future requirements.

In typical cellular mobile communication systems, the base stationbroadcasts on the radio channels certain information which is requiredfor mobile stations to access to the network. In Long-Term Evolution(LTE) and LTE Advanced (LTE-A), such information is called “systeminformation” (“SI”). Each access node, such as an evolved NodeB (“eNB”),or a gNodeB or gNB in the 5G New Radio (NR) System, broadcasts suchsystem information to its coverage area via a Master Information Block(MIB) and several System Information Blocks (SIBs) on downlink radioresources allocated to the access node.

A wireless terminal (“UE”), after entering a coverage area of an eNB orgNB, is required to obtain all the MIB/SIBs which are necessary toaccess to the system. For sake of UEs under coverage, the eNB or gNBperiodically broadcasts all MIB/SIBs relevant for offered services,where each type of MIB or SIBs is transmitted in a designated radioresource(s) with its own pre-determined/configurable frequency.

This all-broadcast-based periodic delivery method (e.g., collectivebroadcast of all SIBs, not just those necessary for system access) isefficient under a condition where many UEs are almost always flowinginto the coverage area (such as a macro cell). However, this approachmay result in wasting valuable radio resources in case of small celldeployment. Therefore, more efficient methods of SIB transmission aredesired.

What is needed, therefore, and an example object of the technologydisclosed herein, are methods, apparatus, and techniques for obtainingand/or updating system information when a wireless terminal is inRRC_CONNECTED state.

SUMMARY OF INVENTION

In one example, a wireless terminal that communicates over a radiointerface with a radio access node of a radio access network (RAN), thewireless terminal comprising: receiver circuitry configured to receive,in a radio resource control (RRC) connected state, one or moreconfiguration messages via dedicated signaling(s), the one or moreconfiguration messages comprising: a timer configuration for a timer,and; a configuration for Physical Downlink Control Channel (PDCCH)monitoring; transmitter circuitry configured to transmit, in the RRCconnected state, a system information (SI) request message to request atleast one system information block (SIB); processor circuitry configuredto: start the timer based on the timer configuration, and; perform an SIacquisition process, wherein; the SI acquisition process comprises:reception of Downlink Control Information (DCI) on PDCCH based on theconfiguration for PDCCH monitoring, and reception of Physical DownlinkShared Channel (PDSCH) scheduled by using the DCI, and; the acquisitionprocess continues until the at least one SIB is successfully received orthe timer expires.

In one example, an access node of a radio access network (RAN), theaccess node comprising: transmitter circuitry configured to transmit, toa wireless terminal in a radio resource control (RRC) connected state,one or more configuration messages via dedicated signaling(s), the oneor more configuration messages comprising: a timer configuration for atimer, and; a configuration for Physical Downlink Control Channel(PDCCH) monitoring; receiver circuitry configured to receive, in the RRCconnected state, a system information (SI) request message to request atleast one system information block (SIB); processor circuitry configuredto perform an SI delivery process, wherein; the SI delivery processcomprises: transmission of Downlink Control Information (DCI) on PDCCHbased on the configuration for PDCCH monitoring, and transmission ofPhysical Downlink Shared Channel (PDSCH) scheduled by using the DCI,and; the timer is configured for the wireless terminal to terminateacquisition of the at least one SIB in a case that the acquisition isunsuccessful.

In one example, a method for a wireless terminal that communicates overa radio interface with a radio access node of a radio access network(RAN), comprising: receiving, in a radio resource control (RRC)connected state, one or more configuration messages via dedicatedsignaling(s), the one or more configuration messages comprising: a timerconfiguration for a timer, and; a configuration for Physical DownlinkControl Channel (PDCCH) monitoring; transmitting, in the RRC connectedstate, a system information (SI) request message to request at least onesystem information block (SIB); starting the timer based on the timerconfiguration, and; performing an SI acquisition process, wherein; theSI acquisition process comprises: reception of Downlink ControlInformation (DCI) on PDCCH based on the configuration for PDCCHmonitoring, and reception of Physical Downlink Shared Channel (PDSCH)scheduled by using the DCI, and; the acquisition process continues untilthe at least one SIB is successfully received or the timer expires.

In one example, a method for an access node of a radio access network(RAN), the method comprising: transmitting, to a wireless terminal in aradio resource control (RRC) connected state, one or more configurationmessages via dedicated signaling(s), the one or more configurationmessages comprising: a timer configuration for a timer, and; aconfiguration for Physical Downlink Control Channel (PDCCH) monitoring;receiving, in the RRC connected state, a system information (SI) requestmessage to request at least one system information block (SIB);performing an SI delivery process, wherein; the SI delivery processcomprises transmission of Downlink Control Information (DCI) on PDCCHbased on the configuration for PDCCH monitoring, and transmission ofPhysical Downlink Shared Channel (PDSCH) scheduled by using the DCI,and; the timer is configured for the wireless terminal to terminateacquisition of the at least one SIB in a case that the acquisition isunsuccessful.

BRIEF DESCRIPTION OF DRAWINGS

The foregoing and other objects, features, and advantages of thetechnology disclosed herein will be apparent from the following moreparticular description of preferred embodiments as illustrated in theaccompanying drawings in which reference characters refer to the sameparts throughout the various views. The drawings are not necessarily toscale, emphasis instead being placed upon illustrating the principles ofthe technology disclosed herein.

FIG. 1 is a diagrammatic view showing transition states of a RadioResource Control RRC state machine.

FIG. 2 is a schematic view showing an example generic communicationssystem comprising a radio access node and a wireless terminal, whereinthe wireless terminal requests, and the radio access node provides,Other system information (Other SI) when the wireless terminal is in aRRC_CONNECTED state.

FIG. 3 is a flowchart showing example, basic example acts or stepsperformed by a wireless terminal of the example generic communicationssystem of FIG. 2 .

FIG. 4 is a diagrammatic view illustrating differing example formats ofa system information block (SIB) which comprises Minimal SI and whichcarries availability of Other system information (Other SI).

FIG. 5 is a diagrammatic view illustrating differing example formats ofa system information block (SIB) which comprises Minimal SI and whichcarries availability of Other system information (Other SI).

FIG. 6 is a diagrammatic view illustrating differing example formats ofa system information block (SIB) which comprises Minimal SI and whichcarries availability of Other system information (Other SI).

FIG. 7 is a diagrammatic view illustrating differing example formats ofa system information block (SIB) which comprises Minimal SI and whichcarries availability of Other system information (Other SI).

FIG. 8 is a diagrammatic view illustrating an exemplary message flow ofon-demand based SI acquisition procedure.

FIG. 9A is a diagrammatic view illustrating three options for an SIrequest procedure.

FIG. 9B is a diagrammatic view illustrating three options for an SIrequest procedure.

FIG. 9C is a diagrammatic view illustrating three options for an SIrequest procedure.

FIG. 10 is a diagrammatic view showing, e.g., a SystemInformationRequestmessage wherein a siRequest information element comprises a bit map.

FIG. 11 is a diagrammatic view illustrating an exemplary message flow ofperiodic broadcast based SI acquisition procedure.

FIG. 12 is a schematic view showing an example generic communicationssystem comprising a wireless terminal configured to detect failure of aSI reception process involving an on-demand SI message, following asuccessful completion of an SI request.

FIG. 13A is a diagrammatic view of differing implementations of SIB1which comprise termination condition parameters.

FIG. 13B is a diagrammatic view of differing implementations of SIB1which comprise termination condition parameters.

FIG. 13C is a diagrammatic view of differing implementations of SIB1which comprise termination condition parameters.

FIG. 13D is a diagrammatic view of differing implementations of SIB1which comprise termination condition parameters.

FIG. 14 is a diagrammatic view illustrating an exemplary message flowincluding an on-demand based SI acquisition procedure which fails.

FIG. 15 is a flowchart showing basic, representative, example acts orsteps performed by the wireless terminal of FIG. 12 .

FIG. 16 is a flowchart showing basic, representative, example acts orsteps performed by the access node of FIG. 12 .

FIG. 17A is a diagrammatic view of a system information acquisitionfailure detector which comprises a SI window counter for making adetermination of SI message acquisition process termination.

FIG. 17B is a diagrammatic view of a system information acquisitionfailure detector which comprises a SI message acquisition process timerfor making a determination of SI message acquisition processtermination.

FIG. 18A is a diagrammatic view showing a common termination conditionfor plural SI messages.

FIG. 18B is a diagrammatic view showing different termination conditionsfor different SI messages.

FIG. 19 is a schematic view showing an example generic communicationssystem comprising a wireless terminal configured to detect failure of aSI reception process involving a periodically broadcasted SI message.

FIG. 20 is a diagrammatic view illustrating an exemplary message flowincluding a failed SI acquisition procedure for a periodicallybroadcasted SI message.

FIG. 21 is a flowchart showing basic, representative, example acts orsteps performed by the wireless terminal of FIG. 19 .

FIG. 22 is a flowchart showing basic, representative, example acts orsteps performed by the access node of FIG. 19 .

FIG. 23 is a schematic view showing an example communications systemcomprising a radio access node and a wireless terminal, wherein thewireless terminal terminates a SI message acquisition process based on anumber of modification periods.

FIG. 24 is a diagrammatic view of a series of modification periods andshowing generation and transmission of system information windowsthrough plural modification periods.

FIG. 25 is a flowchart showing basic, representative, example acts orsteps performed by the wireless terminal of FIG. 23 .

FIG. 26 is a flowchart showing basic, representative, example acts orsteps performed by the access node of FIG. 23 .

FIG. 27 is a schematic view showing an example communications systemcomprising a radio access node and a wireless terminal, wherein thewireless terminal uses both first type system information and secondtime system information and terminates a SI message acquisition processfor the second type system information based on a number of modificationperiods.

FIG. 28 is a schematic view showing an example communications systemcomprising a radio access node and a wireless terminal, wherein thewireless terminal is required to wait an offset value of time beforestarting an SI message acquisition process.

FIG. 29 is a flowchart showing basic, representative, example acts orsteps performed by the wireless terminal of FIG. 28 .

FIG. 30 is a flowchart showing basic, representative, example acts orsteps performed by the access node of FIG. 28 .

FIG. 31 is a diagrammatic view illustrating an exemplary message flowincluding for the communications system of FIG. 28 .

FIG. 32 is a schematic view showing an example communications systemcomprising a radio access node and a wireless terminal, wherein thewireless terminal terminates a SI message acquisition process based on anumber of transmission opportunities.

FIG. 33 is a flowchart showing basic, representative, example acts orsteps performed by the wireless terminal of FIG. 32 .

FIG. 34 is a flowchart showing basic, representative, example acts orsteps performed by the access node of FIG. 32 .

FIG. 35 is a schematic view showing an example communications systemwhich is a special case of the system of FIG. 32 .

FIG. 36A is a diagrammatic view showing example scenarios of performinga system information message acquisition process when transmissionopportunities are system information windows.

FIG. 36B is a diagrammatic view showing example scenarios of performinga system information message acquisition process when transmissionopportunities are system information windows.

FIG. 37 is a diagrammatic view showing an example scenario of performinga system information message acquisition process when transmissionopportunities are modification periods.

FIG. 38 is a schematic view showing an example communications systemcomprising a radio access node and a wireless terminal, wherein thewireless terminal requests on-demand system information in connectedstate.

FIG. 39A is a diagrammatic view of actions which may occur in an examplescenario performed by the system of FIG. 38 wherein on-demand systeminformation is successfully acquired.

FIG. 39B is a diagrammatic view of actions which may occur in an examplescenario performed by the system of FIG. 38 wherein on-demand systeminformation is not successfully acquired.

FIG. 40 shows representative, basic acts or steps performed by awireless terminal of FIG. 38 in an on-demand based SIB/SI messagedelivery procedure in RRC_CONNECTED state.

FIG. 41 shows representative, basic acts or steps performed by an accessnode of FIG. 38 in an on-demand based SIB/SI message delivery procedurein RRC_CONNECTED state.

FIG. 42 is a diagrammatic view showing example electronic machinerywhich may comprise node electronic machinery or terminal electronicmachinery.

DESCRIPTION OF EMBODIMENTS

In one of its example aspects, the technology disclosed herein concernsa wireless terminal that communicates over a radio interface with aradio access node of a radio access network (RAN). The wireless terminalcomprises receiver circuitry, transmitter circuitry, and processorcircuitry. The receiver circuitry is configured to receive, in a radioresource control (RRC) connected state, one or more configurationmessages via dedicated signaling(s). The one or more configurationmessages may comprise a timer configuration for a timer and aconfiguration for Physical Downlink Control Channel (PDCCH) monitoring.The transmitter circuitry is configured to transmit, in the RRCconnected state, a system information (SI) request message to request atleast one system information block (SIB). The processor circuitry isconfigured to start the timer based on the timer configuration and toperform an SI acquisition process. In an example embodiment and mode,the SI acquisition process comprises reception of Downlink ControlInformation (DCI) on PDCCH based on the configuration for PDCCHmonitoring, and reception of Physical Downlink Shared Channel (PDSCH)scheduled by using the DCI. The SI acquisition process continues untilthe at least one SIB is successfully received or until the timerexpires. Methods for operating such wireless terminal are also provided.

In another of its example aspects the technology disclosed hereinconcerns an access node which communicates over a radio interface with awireless terminal. In an example embodiment and mode the access nodecomprises transmitter circuitry, receiver circuitry, and processorcircuitry. The transmitter circuitry is configured to transmit, to awireless terminal in a radio resource control (RRC) connected state, oneor more configuration messages via dedicated signaling(s). The one ormore configuration messages may comprise (1) a timer configuration for atimer, and (2) a configuration for Physical Downlink Control Channel(PDCCH) monitoring. The receiver circuitry is configured to receive, inthe RRC connected state, a system information (SI) request message torequest at least one system information block (SIB). The processorcircuitry is configured to perform an SI delivery process. The SIdelivery process comprises: (1) transmission of Downlink ControlInformation (DCI) on PDCCH based on the configuration for PDCCHmonitoring, and transmission of Physical Downlink Shared Channel (PDSCH)scheduled by using the DCI. The timer is configured for the wirelessterminal to terminate acquisition of the at least one SIB in a case thatthe acquisition is unsuccessful. Methods of operating such access nodeare also disclosed.

In the following description, for purposes of explanation and notlimitation, specific details are set forth such as particulararchitectures, interfaces, techniques, etc. in order to provide athorough understanding of the technology disclosed herein. However, itwill be apparent to those skilled in the art that the technologydisclosed herein may be practiced in other embodiments that depart fromthese specific details. That is, those skilled in the art will be ableto devise various arrangements which, although not explicitly describedor shown herein, embody the principles of the technology disclosedherein and are included within its spirit and scope. In some instances,detailed descriptions of well-known devices, circuits, and methods areomitted so as not to obscure the description of the technology disclosedherein with unnecessary detail. All statements herein recitingprinciples, aspects, and embodiments of the technology disclosed herein,as well as specific examples thereof, are intended to encompass bothstructural and functional equivalents thereof. Additionally, it isintended that such equivalents include both currently known equivalentsas well as equivalents developed in the future, i.e., any elementsdeveloped that perform the same function, regardless of structure.

Thus, for example, it will be appreciated by those skilled in the artthat block diagrams herein can represent conceptual views ofillustrative circuitry or other functional units embodying theprinciples of the technology. Similarly, it will be appreciated that anyflow charts, state transition diagrams, pseudocode, and the likerepresent various processes which may be substantially represented incomputer readable medium and so executed by a computer or processor,whether or not such computer or processor is explicitly shown.

As used herein, the term “core network” can refer to a device, group ofdevices, or sub-system in a telecommunication network that providesservices to users of the telecommunications network. Examples ofservices provided by a core network include aggregation, authentication,call switching, service invocation, gateways to other networks, etc.

As used herein, the term “wireless terminal” can refer to any electronicdevice used to communicate voice and/or data via a telecommunicationssystem, such as (but not limited to) a cellular network. Otherterminology used to refer to wireless terminals and non-limitingexamples of such devices can include user equipment terminal, UE, mobilestation, mobile device, access terminal, subscriber station, mobileterminal, remote station, user terminal, terminal, subscriber unit,cellular phones, smart phones, personal digital assistants (“PDAs”),laptop computers, netbooks, e-readers, wireless modems, etc.

As used herein, the term “access node”, “node”, or “base station” canrefer to any device or group of devices that facilitates wirelesscommunication or otherwise provides an interface between a wirelessterminal and a telecommunications system. A non-limiting example of abase station can include, in the 3GPP specification, a Node B (“NB”), anenhanced Node B (“eNB”), a home eNB (“HeNB”), a 5G (New Radio [NR])gNodeB or gNB, or some other similar terminology. Another non-limitingexample of a base station is an access point. An access point may be anelectronic device that provides access for wireless terminal to a datanetwork, such as (but not limited to) a Local Area Network (“LAN”), WideArea Network (“WAN”), the Internet, etc. Although some examples of thesystems and methods disclosed herein may be described in relation togiven standards (e.g., 3GPP Releases 8, 9, 10, 11, 12, or higher), thescope of the present disclosure should not be limited in this regard. Atleast some aspects of the systems and methods disclosed herein may beutilized in other types of wireless communication systems.

As used herein, the term “telecommunication system” or “communicationssystem” can refer to any network of devices used to transmitinformation. A non-limiting example of a telecommunication system is acellular network or other wireless communication system.

As used herein, the term “cellular network” can refer to a networkdistributed over cells, each cell served by at least one fixed-locationtransceiver, such as a base station. A “cell” may be any communicationchannel that is specified by standardization or regulatory bodies to beused for International Mobile Telecommunications-Advanced(“IMTAdvanced”). All or a subset of the cell may be adopted by 3GPP aslicensed bands (e.g., frequency band) to be used for communicationbetween a base station, such as a Node B, and a UE terminal. A cellularnetwork using licensed frequency bands can include configured cells.Configured cells can include cells of which a UE terminal is aware andin which it is allowed by a base station to transmit or receiveinformation.

As used herein, “system information” (“SI”) may include a MasterInformation Block (MIB) and several System Information Blocks (SIB s)which are provided on downlink radio resources allocated to an accessnode. The system information may be broadcast, and some types of systeminformation may be provided on demand, e.g., upon receipt of a requestfor system information from a wireless terminal.

In various aspects of the technology disclosed herein, systeminformation is classified into plural categories or types. In an exampleembodiment and mode, first type of the system information (e.g. a firsttype SIB or SIB1) is Minimum System Information (Minimum SI), minimallycontaining information required for UEs initially access to the network,periodically broadcasted by each access node (e.g. eNB for LTE, gNB for5G Radio System). In some configurations, Minimum System SI may consistof MIB and a limited number of SIBs. The MIB may contain essentialinformation for the radio system to help wireless terminals tosynchronize to the serving access node and may also contain instructionhow to obtain at least one of the essential SIBs. The Minimum SI may bealso referred as “essential SI”, or first type system information.

Second type of system information, e.g., “Other system information,“Other SI”, or second type system information, contains all the othertypes of information, i.e., all types of system information except theMinimum System Information. The Other SI may comprise several systeminformation blocks (SIBs) that are not categorized as Minimum SI. TheOther SI may be also referred as “non-essential SI”. However, secondtype system information is not to be confused with SIB Type 2, which isa particular (second) system information block (SIB) that may beincluded in the Minimum System Information or may be a part of the OtherSI.

In some example embodiment and modes described herein, for each of theSIBs the access node may choose to broadcast the SIB periodically,similar to the SIBs in Minimum SI. Alternatively, the access node maychoose to refrain from transmitting the SIB until receiving a request ofon-demand delivery from a UE. In this case, the access node mayadvertise the availability of on-demand delivery using Minimum SI.

As described herein, both an access node and a wireless terminal maymanage respective Radio Resource Control (RRC) state machines. The RRCstate machines transition between several RRC states including RRC_IDLE,RRC_INACTIVE and RRC_CONNECTED. FIG. 1 depicts the state transitiondiagram of the RRC states. From the vantage point of a wireless terminale.g., user equipment (UE), the RRC states may be briefly characterizedas follows:

RRC_IDLE:

-   -   A UE specific DRX (discontinuous reception) may be configured by        upper layers;    -   UE controlled mobility based on network configuration;    -   The UE:        -   Monitors a Paging channel;        -   Performs neighboring cell measurements and cell            (re-)selection;        -   Acquires system information.

RRC_INACTIVE:

-   -   A UE specific DRX may be configured by upper layers or by RRC        layer;    -   UE controlled mobility based on network configuration;    -   The UE stores the Access Stratum (AS) context;    -   The UE:        -   Monitors a Paging channel;        -   Performs neighboring cell measurements and cell            (re-)selection;        -   Performs RAN-based notification area updates when moving            outside the RAN-based notification area;        -   Acquires system information.

RRC_CONNECTED:

-   -   The UE stores the AS context.    -   Transfer of unicast data to/from UE.    -   At lower layers, the UE may be configured with a UE specific        DRX;    -   Network controlled mobility, i.e. handover within NR and to/from        E-UTRAN.;    -   The UE:        -   Monitors a Paging channel;        -   Monitors control channels associated with the shared data            channel to determine if data is scheduled for it;        -   Provides channel quality and feedback information;        -   Performs neighboring cell measurements and measurement            reporting;        -   Acquires system information.

The technology disclosed herein concerns, e.g., apparatus, methods, andprocedures for obtaining and/or updating SIBs including controllingtiming of an SI message acquisition process.

FIG. 2 shows an example communications system 20 wherein radio accessnode 22 communicates over air or radio interface 24 (e.g., Uu interface)with wireless terminal 26. As mentioned above, the radio access node 22may be any suitable node for communicating with the wireless terminal26, such as a base station node, or eNodeB (“eNB”) or gNodeB (“gNB”),for example. The node 22 comprises node processor circuitry (“nodeprocessor 30”) and node transceiver circuitry 32. The node transceivercircuitry 32 typically comprises node transmitter circuitry 34 and nodereceiver circuitry 36, which are also called node transmitter and nodereceiver, respectively.

The wireless terminal 26 comprises terminal processor 40 and terminaltransceiver circuitry 42. The terminal transceiver circuitry 42typically comprises terminal transmitter circuitry 44 and terminalreceiver circuitry 46, which are also called terminal transmitter 44 andterminal receiver 46, respectively. The wireless terminal 26 alsotypically comprises user interface 48. The terminal user interface 48may serve for both user input and output operations, and may comprise(for example) a screen such as a touch screen that can both displayinformation to the user and receive information entered by the user. Theuser interface 48 may also include other types of devices, such as aspeaker, a microphone, or a haptic feedback device, for example.

For both the radio access node 22 and radio interface 24, the respectivetransceiver circuitries 22 include antenna(s). The transmitter circuit34 and transmitter circuit 44 may comprise, e.g., amplifier(s),modulation circuitry and other conventional transmission equipment. Thereceiver circuit 36 and receiver circuit 46 may comprise, e.g., e.g.,amplifiers, demodulation circuitry, and other conventional receiverequipment.

In general operation, access node, 22 and wireless terminal 26communicate with each other across radio interface 24 using predefinedconfigurations of information. By way of non-limiting example, the radioaccess node 22 and wireless terminal 26 may communicate over radiointerface 24 using “frames” of information that may be configured toinclude various channels. In Long Term Evolution (LTE), for example, aframe, which may have both downlink portion(s) and uplink portion(s),may comprise plural subframes, with each LTE subframe in turn beingdivided into two slots. The frame may be conceptualized as a resourcegrid (a two dimensional grid) comprised of resource elements (RE). Eachcolumn of the two dimensional grid represents a symbol (e.g., an OFDMsymbol on downlink (DL) from node to wireless terminal; an SC-FDMAsymbol in an uplink (UL) frame from wireless terminal to node). Each rowof the grid represents a subcarrier. The frame and subframe structureserves only as an example of a technique of formatting of informationthat is to be transmitted over a radio or air interface. It should beunderstood that “frame” and “subframe” may be utilized interchangeablyor may include or be realized by other units of information formatting,and as such may bear other terminology (such as blocks, for example).

To cater to the transmission of information between radio access node 22and wireless terminal 26 over radio interface 24, the node processor 30and terminal processor 40 of FIG. 2 are shown as comprising respectiveinformation handlers. For an example implementation in which theinformation is communicated via frames, the information handler forradio access node 22 is shown as node frame/signal scheduler/handler 50,while the information handler for wireless terminal 26 is shown asterminal frame/signal handler 52.

The node processor 30 of radio access node 22 also includes systeminformation (SI) generator 54. As described above, at least some of thesystem information generated and provided by the system information (SI)generator 54 is Minimum System Information (Minimum SI), also known asfirst type system information, represented by Minimum SI handler 54M.Some of the system information may be Other system information (OtherSI), also known as second type system information, represented by OtherSI handler 540 in FIG. 2 . The wireless terminal 26 uses the systeminformation (SI) generated by radio access node 22. Some of the MinimumSI may inform the wireless terminal 26 of the availability of the OtherIS.

FIG. 2 illustrates a generic message 2-1 by which the node radioresource controller 54 may supply the Minimal SI to wireless terminal26. In some example implementations, upon knowing of the availability ofthe Other SI, due to the message 2-1, for example, the wireless terminal26 specifically requests the Other system information, in on-demandfashion, as described herein. The terminal processor 40 of wirelessterminal 26 comprises, e.g., SI processor 56, to facilitate obtainingand use of system information.

The technology disclosed herein concerns, e.g., apparatus, methods, andprocedures for obtaining and/or updating system information blocks(SIBs) in/of the Other SI (Other SI SIBs) in on-demand basis. Since inat least some of the example embodiments and modes the technologydisclosed herein involves the Radio Resource Control (RRC) procedures,FIG. 2 shows terminal processor 40 as comprising node radio resourcecontrol (RRC) controller 60, e.g., node RRC controller 60. The node RRCcontroller 60 may execute an instance of the RRC state machine for eachwireless terminal in which the access node 20 is in communication, witheach instance keeping track of the RRC state transitions experienced bythe wireless terminal associated with the respective instance.

FIG. 2 also shows the terminal processor 40 of wireless terminal 26 ascomprising, in addition to terminal SI processor 56, a terminal RRCcontroller 70. The terminal RRC controller 70 includes or executes theRRC state machine discussed above, which transitions through the RRCstates, as described above and shown in FIG. 2 , for a communicationinvolving wireless terminal 26.

FIG. 2 thus shows that the access node 22 comprises node processor 30,e.g., node processor circuitry 30, transmitter circuit 34, and, receivercircuit 36. The transmitter circuit 34 is configured to transmit thefirst type system information over a radio interface, the first typesystem information including availability of a SI message belonging tothe second type system information. The receiver circuit 36 isconfigured to receive from the wireless terminal a request message torequest delivery of the SI message which is available by on-demandbasis. The transmitter circuit 34 is further configured to transmit theSI message to the wireless terminal.

FIG. 2 thus shows that the wireless terminal 26 communicates over radiointerface 24 with access nodes, such as access node 22, of a radioaccess network (RAN). The wireless terminal 26 comprises receivercircuit 46, transmitter circuit 44, and terminal processor 40, e.g.,terminal processor circuitry. The receiver circuit 46 is configured toreceive first type system information over the radio interface. Theterminal processor circuitry is configured to generate a request messageto request the second type SIB which is available in an on-demand basis.The transmitter circuit 44 is configured to transmit the request messageover the radio interface while in the connected state. The receivercircuit 46 is also configured to receive the SI message while in theconnected state.

FIG. 3 shows example, representative acts or steps performed inconjunction with a generic method of operating a wireless terminal of aradio access network (RAN), such as wireless terminal 26 of FIG. 2 . Act3-1 comprises the wireless terminal acquiring, e.g., receiving, theMinimum SI that is broadcasted from the currently serving access node,e.g., access node 22. The Minimum SI may be broadcast in a message suchas message 2-1 of FIG. 2 . The Minimum SI may contain information aboutthe Other SI, including the delivery method, e.g., periodicbroadcast/on-demand, scheduling information, validity information, etc.Based on the information, the wireless terminal in act 3-2 may determinewhich SI message(s) to acquire by on-demand. As act 3-3, the wirelessterminal may send a request message (depicted as message 2-2 of FIG. 2 )to the access node, the request message indicating the SI message(s)that the wireless terminal desires to obtain. As act 3-4 the wirelessterminal 26 may attempt to receive the requested SI message(s) which,e.g., was sent using message 2-3 of FIG. 2 .

It was mentioned above that the first type system information includesavailability of a SI message belonging to the second type systeminformation, that the request message requests delivery of a SI messagewhich is available by on-demand basis, and that the SI message istransmitted to the wireless terminal. It should be understood thatreference herein to “a SI message belonging to the second type systeminformation” means one or more pieces of Other system information (OtherSI), e.g., one or more SI messages belonging to the second type systeminformation. In some example situations indeed only one SI message maybe advertised as available and accordingly periodically broadcasted orrequested on-demand. But in other example situations plural SI messages(e.g., plural pieces of Other SI) are advertised as available, some ofwhich may be periodically broadcasted and the others may be requestedon-demand. Furthermore, it should be noted that in some configurations(e.g. the configuration presented in FIG. 7 , or in FIG. 13A-D) theavailability may be included in the scheduling information (e.g.schedulingInfoList described below).

In some configurations, the availability and delivery method informationfor Other SI SIBs may be included in SIB Type 1, one of the SIBs in theMinimum SI. FIG. 4 shows an example format of SIB Type 1, includingschedulingInfoList, si-WindowLength, otherSIBInfoList, validity areaidentification (si-AreaID), and possibly other configuration parameters.The otherSIBInfoList is a list of otherSIBInfo, which comprisesSIB-Type, an identifier of a SIB, validityInfo and validity informationof the SIB (a value tag [valueTag], and other parameters, such asvalidity timer, etc.).

SIBs other than SIB1 are carried in SystemInformation (SI) messages andmapping of SIBs to SI messages is flexibly configurable byschedulingInfoList included in SIB1, with restrictions that: each SIB iscontained only in a single SI message, only SIBs having the saescheduling requirement (periodicity given by si-periodicity) can bemapped to the same SI message. There may be multiple SI messagestransmitted with the same periodicity.

In one configuration, each element, schedulingInfo, ofschedulingInfoList may represent one SI message, comprising itsperiodicity (si-Periodicity), delivery method (deliveryMethod)indicating if this SIB is periodically broadcasted or to be transmittedupon request (on-demand), and associated SIB types (one or moreSIB-Type's). The actual broadcast opportunity, e.g., timing/resources,of a given SI message may be determined by a pre-determined or anetwork-configured formula as a function of at least the correspondingperiodicity. At each opportunity the broadcast of the SI message mayoccur within the duration of the window length (si-WindowLength).Hereafter a broadcast opportunity is also referred as a SI window. Morethan one SIB may be possibly transmitted on a same SI window.

In the configuration of FIG. 4 si-AreaID is common for all SI messagesor SIB types, which means that all SIBs have the same validity area.Alternatively, in another configuration, each SI message may have adesignated validity area. FIG. 5 shows an example format of SIB1 forsuch a configuration wherein each SI message may have a designatedvalidity area. Furthermore, in another configuration, having an exampleformat such as shown in FIG. 6 , each SIB type may have a designatedvalidity area. Thus, in differing implementations, the systeminformation (SI) generator 54 of FIG. 2 , working with node frame/signalscheduler/handler 50, generates the differing formatted SI messages ofFIG. 4 , FIG. 5 , and FIG. 6 , for transmission by node transmittercircuitry 34 over radio interface 24.

FIG. 7 is an alternative format for SIB1, which is logically equivalentto the format shown in FIG. 4 . The si-BroadcastStatus informationelement of FIG. 7 may be functionally identical to deliveryModeinformation element described earlier. In one configuration, theinformation element sibValueTagList may comprise a list of value tagsfor the available SIBs included in schedulingInfoList, in the order ofthe SIB numbering scheme (e.g. SIB2, SIB3, SIB4, SIB5, . . . ). Inanother configuration, sibValueTagList may comprise a list of value tagsfor the available SIBs (included in schedulingInfoList) as well as thenon-available SIBs (not included in schedulingInfoList), in the order ofthe SIB numbering scheme (e.g. SIB2, SIB3, SIB4, SIB5, . . . ). In thiscase, a pre-determined value may be set to the value tag for anon-available SIB. Accordingly, the si-BroadcastStatus informationelement may be used for indicating broadcast status (e.g. the broadcaststatus being either periodic broadcast or on-demand basis). FIG. 8 is anexemplary message flow diagram of on-demand based SI acquisitionprocedure. As shown by act 8-0, wireless terminal 26 in either RRC_IDLE,RRC_INACTIVE or RRC_CONNECTED state stores the content of SIB #A withthe validity information, valueTag=a, si-AreaID=2, which the wirelessterminal has previously received. From the currently serving accessnode, as act 8-1 the wireless terminal may obtain SIB1 as Minimum SI. Asshown in FIG. 4 , FIG. 5 , FIG. 6 , and FIG. 7 , the SIB1 includes thescheduleInfoList, which in turn may include one or more schedulingInfoinformation elements. An example scheduleInfoList for this scenario isshown in Table 1, wherein the k'th schedulingInfo indicates that the SImessage associated with this schedulingInfo (SI #k, hereafter),containing SIB #A, will be available by on-demand delivery. Furthermore,the otherSIBInfo corresponding to SIB #A indicates that the validityinformation of SIB #A is valueTag=b, si-AreaID=3. It is assumedhereafter that whenever the wireless terminal receives SIB1, it hasalready received MIB beforehand.

TABLE 1 ... schedulingInfoList {  ...  k'th schdulingInfo (SI#k) {  ... deliveryMethod = on-demand  SIB-type = A  ...  }  ...  } } ...otherSIBInfoList {  ...  otherISBInfo {   SIB-type = A   ValidityInfo {   valueTag = b    ...   }   ...  }  ... } ... si-AreaID = 3 ...

Knowing that the stored SIB #A is now invalid, the wireless terminal maydecide to obtain a valid version of SIB #A, and may initiate the SIrequest procedure represented by act 8-2 and explained herein. After theSI request procedure has a successful result, the wireless terminal maystart the SI message acquisition, shown generally as act 8-3 in FIG. 8 .In the SI message acquisition the wireless terminal monitors signalsfrom the access node in the designated SI windows derived from thescheduling information (scheduleInfo) in the SIB1, and thereby attemptsto receive the requested SI #k. The SI windows are shown by dottedrectangles in FIG. 8 . FIG. 8 shows by act 8-3 a a first transmission ofthe requested SI #k, which is unsuccessful, and by act 8-3 b a secondtransmission of the requested SI #k, which is successful. A tail of avertical down-pointing arrow in the SI message acquisition depiction ofFIG. 8 is associated with start of the SI message acquisition, while thehead of the same vertical down-pointing arrow is associated with end ofthe SI message acquisition (at successful reception of the SI #k). FIG.8 also shows by act 8-4 that other transmissions of the requested systeminformation may also be made even after the wireless terminal hassuccessfully received the sought SI #k.

In one configuration, the wireless terminal may use a counter, which isincremented at every SI window of a particular SI message, e.g. SI #k.In this configuration, the SI message acquisition may end when therequested SI message(s) are successfully received, or when the counterreaches a maximum counter value. In another configuration the wirelessterminal starts a timer at the beginning of the SI message acquisition.In this configuration, the SI message acquisition may end when therequested SI message(s) are successfully received, or when the timerexpires. The maximum counter value, or the timer value, which may becommon for all SI messages or per-SI message basis, may bepre-configured or configured by network via system information. Theconditions for the wireless terminal to end the SI reception process isreferred as “termination conditions” herein.

FIG. 9A, FIG. 9B and FIG. 9C show three options for the SI requestprocedure. In FIG. 9A, which may be applicable to wireless terminals inany of the RRC states, the request of on-demand delivery for SI messagesmay be accomplished by sending a Random Access Preamble, which maycomprise a sequence selected from a set of available sequencesconfigured by the access node via Minimum SI. A given sequence isidentified by a Preamble Index. When the access node detects thetransmission of a preamble sequence, it may respond to it with RandomAccess Response, which includes the Preamble Index corresponding to thesequence. Upon receiving the Random Access Response, the wirelessterminal may validate that the Preamble index in the Random AccessResponse matches the one associated with the preamble sequence, and thensend to the access node SystemInformationRequest message that includesthe identity of the SI messages (e.g. SI #k) that the wireless terminaldesires to receive. In response, the access node may send aSystemInformation message acknowledging the request, indicating that therequested SI message(s) will be broadcasted from the next SI windowscheduled for the requested SI message(s).

In one configuration, the access node may include in Minimum SI a set ofPreamble indices, each of which is designated for requesting on-demanddelivery of one or more specific SI messages. FIG. 9B illustrates anexample SI request procedure using this configuration, where thewireless terminal in any RRC state may transmit Random Access Preamblesequence given by the Preamble Index associated with the SI message(s)that the wireless terminal has selected. When the wireless terminalreceives Random Access Response including the Preamble Index, it mayconsider that the request procedure is successful.

The SI request procedure in FIG. 9C may be applicable to wirelessterminals in RRC_CONNECTED, wherein the SystemInformationRequest messageis sent without the random access preamble/response.

In any of the three options disclosed above, the wireless terminal mayproceed to the SI message acquisition if the SI request procedure issuccessful. Otherwise, the wireless terminal may think that the servingcell (controlled by the access node) is barred, which will invoke a cellreselection.

The SystemInformationRequest message shown in FIG. 9A or FIG. 9C mayinclude an information element (e.g. siRequest) to indicate which SImessage(s) that the wireless terminal desires to receive. In oneconfiguration, as shown in FIG. 10 , the siRequest may comprise a bitmap, wherein each bit corresponds to a schedulingInfo informationelement in SIB1 of the current serving cell, the bits arranged in theorder of schedulingInfo information elements. By doing so, each bit ofthe bit map may correspond to a specific SI message. Alternatively,siRequest may carry a field indicating that the wireless terminaldesires to receive at least one on-demand basis SI message. In thiscase, the access node may start broadcasting all of the on-demand basisSI messages for a pre-configured duration. The SystemInformation messageshown in FIG. 9A or FIG. 9C may include siAck, an information elementfor acknowledging siRequest. In one configuration, siAck may comprisesthe same bit map as the one in SystemInformationRequest, indicating theSI message(s) to be broadcasted. Alternatively, siAck may comprise oneBoolean field, indicating whether the request has been accepted or not.

FIG. 11 is an exemplary message flow diagram of SI acquisition procedurefor a SI message broadcasted periodically. Act 11-0 comprises thewireless terminal 26, in either RRC_IDLE, RRC_INACTIVE or RRC_CONNECTEDstate, storing the content of SIB #A with the validity information,e.g., valueTag=a and si-AreaID=2. Act 11-1 comprises the wirelessterminal 26 obtaining, from the currently serving access node 22, SIB1as Minimum SI, which, as understood from previous description, includesone or more schedulingInfo information elements. In the scenario of FIG.11 , and as shown by Table 2, the k'th schedulingInfo informationelement indicates that the SI message associated with thisschedulingInfo (SI #k, hereafter), containing SIB #A, is currentlybroadcasted periodically. Furthermore, the SIB1 specifies (see Table 2)that otherSIBInfo corresponding to SIB #A indicates that the validityinformation of SIB #A is now valueTag=b and si-AreaID=3.

Knowing that the stored SIB #A is now invalid, as act 11-3 the wirelessterminal 26 begins an SI message acquisition wherein the wirelessterminal may attempt to acquire the SI message (SI #k) in the SI windowsspecified in SIB 1. In FIG. 11 , act 11-3 a illustrates an unsuccessfulSI message reception attempt in a first SI window for SI #k, followed byact 11-3 b which is a successful SI message reception in a second SIwindow for SI #k, Thus, as shown in FIG. 11 , if the SI message is notreceived by the end of the SI window (as was the case for act 11-3 a),the wireless terminal 26 may repeat reception at the next SI windowoccasion for the concerned SI message until it successfully receives theSI message (as was done in act 11-3 b).

TABLE 2 ... schedulingInfoList {  ...  k'th schdulingInfo (SI#k) {  ... deliveryMethod = broadcast  SIB-type = A  ...  }  ...  } } ...otherSIBInfoList {  ...  otherISBInfo {   SIB-type = A   ValidityInfo {   valueTag = b    ...   }   ...  }  ... } ... si-AreaID = 3 ...

Unsuccessful Attempted Reception of on-Demand System Information

FIG. 12 shows an example communications system 20(12) comprisingwireless terminal 26(12) configured to detect failure of a SI receptionprocess involving an on-demand SI message, following a successfulcompletion of an SI request. The access node 22(12) and wirelessterminal 26(12) of FIG. 12 are essentially identical to the respectiveaccess node 22 and wireless terminal 26 of FIG. 2 , except as otherwiseindicated herein. In terms of likeness, for example, the radio accessnode 22(12) comprises node processor 30 and node transceiver circuitry32, with the node processor 30 comprising, e.g., node frame/signalscheduler/handler 50, system information (SI) generator 54, and node RRCcontroller 60. Similarly, the wireless terminal 26(12) comprisesterminal processor 40, terminal transceiver circuitry 42, with terminalprocessor 40 comprising terminal frame/signal scheduler/handler 52,system information (SI) processor 56, and terminal RRC controller 70.

FIG. 12 also shows that wireless terminal 26(12) comprises systeminformation acquisition failure detector 80. The terminal processor 40,and particularly SI processor 56, may comprise or constitute the systeminformation acquisition failure detector 80. The system informationacquisition failure detector 80 is configured to make a determination ofa failure of the SI message acquisition process. The system informationacquisition failure detector 80 may make such failure determinationbased on a termination condition, as herein explained.

The system information generator 54 of radio access node 22(12) isconfigured to generate first type system information. For the exampleembodiment and mode of FIG. 12 , and in an example, non-limiting mannershown in FIG. 13 , the first type system information comprises(information elements or the like which indicate): availability ofsecond type SI messages; scheduling information of each of the SImessages; a delivery mode for each of the second type SI messages; and,a configuration parameter to configure at least one terminationcondition for determination of a failure of an SI message acquisitionprocess for the on-demand based second type SI messages.

As understood herein, a second type SI message comprises at least onesystem information block (SIB), and the delivery mode may be eitherperiodic broadcast or on-demand basis. The transmitter circuitry 36 ofradio access node 22(12) is configured to transmit the first type systeminformation over the radio interface 24 to the wireless terminal 26(12),as shown by arrow 12-1 in FIG. 12

As in the example embodiment and mode of FIG. 2 , the on-demand Other SIrequest generator 72 of wireless terminal 26(12) may request at leastone second type SI using a request message as indicated by arrow 12-2 inFIG. 12 . The second type SI request message depicted by arrow 12-2 isreceived by node receiver circuitry 36. The node processor 30, andparticularly the SI generator 54, generates the requested (second type)SI message in one or more windows of transmission, the transmission ofthe requested SI message being depicted by arrow 12-3 in FIG. 12 .

As mentioned above, system information acquisition failure detector 80may make a determination of a failure of the SI message acquisitionprocess. When so doing, in an example embodiment and mode, the terminalprocessor 40, working in response to or with system informationacquisition failure detector 80, is configured to initiate acquisitionof the first type system information. That is, the terminal processor 40is configured, upon a failure of the SI message acquisition process, toinitiate acquisition of the first type system information, e.g., toagain request the first type system information (Minimum SI) from theradio access node 22(12). In FIG. 12 such request for first type systeminformation is depicted by arrow 12-4.

FIG. 13A is an exemplary format of SIB1, which is based on the formatshown in FIG. 7 with an additional information elementsi-MaxAcqAttempts. The information element si-MaxAcqAttempts provides atermination condition for the SI message acquisition, indicating themaximum number of SI message reception opportunities (e.g. SI windows)allowed before the end of the SI message acquisition. FIG. 13B is analternative format of SIB1, wherein the information elementue-TimersAndConstants includes a timer configuration (T #x) to be usedas a termination condition for the SI message acquisition.

FIG. 14 is an exemplary message flow diagram of on-demand based SIacquisition procedure wherein system information acquisition failure isdetected. As shown by act 14-0, wireless terminal 26, in eitherRRC_IDLE, RRC_INACTIVE or RRC_CONNECTED state stores the content of SIB#A with the validity information, valueTag=a, si-AreaID=2, which thewireless terminal has previously received. From the currently servingaccess node, as act 14-1 the wireless terminal may obtain SIB1 asMinimum SI, e.g., first type system information. Obtaining of the SIB1is depicted by arrow 12-1 in FIG. 12 . As shown in FIG. 13 , the SIB1includes the scheduleInfoList, which in turn may include one or moreschedulingInfo information elements. An example scheduleInfoList forthis scenario is shown in previously-discussed Table 1, wherein the k'thschedulingInfo indicates that the SI message associated with thisschedulingInfo (SI #k, hereafter), containing SIB #A, will be availableby on-demand delivery. Furthermore, the otherSIBInfo corresponding toSIB #A indicates that the validity information of SIB #A is valueTag=b,si-AreaID=3. It is assumed hereafter that whenever the wireless terminalreceives SIB1, it has already received MIB beforehand.

Knowing that the stored SIB #A is now invalid, the wireless terminal maydecide to obtain a valid version of SIB #A, and may initiate the SIrequest procedure represented by act 14-2 and explained herein andillustrated by arrow 12-2 in FIG. 12 . After the SI request procedurehas a successful result, the wireless terminal may start the SI messageacquisition, shown generally as act 14-3 in FIG. 14 . In the SI messageacquisition the wireless terminal monitors signals from the access node(depicted by arrow 12-3 in FIG. 12 ) in the designated SI windowsderived from the scheduling information (scheduleInfo) in the SIB1, andthereby attempts to receive the requested SI #k. The SI windows areshown by dotted rectangles in FIG. 14 . FIG. 14 shows by act 14-3 a, act14-3 b, and act 14-3 c three successive transmissions of the requestedSI #k, all of which are unsuccessful. A tail of a vertical down-pointingarrow in the SI message acquisition depiction of FIG. 14 is associatedwith start of the SI message acquisition, while the head of the samevertical down-pointing arrow is associated with end of the SI messageacquisition. In FIG. 14 , the SI message acquisition fails. Failure ofthe SI message acquisition is determined by system informationacquisition failure detector 80 which, as indicated above, makes adetermination of a failure of the SI message acquisition process basedon a termination condition. Examples of the termination condition aredescribed below.

Upon detection of failure of the SI message acquisition process, as act14-4 the terminal processor 40 initiates (re)acquisition of the firsttype system information, e.g., the MINIMAL SI or SIB1, as shown by arrow12-4 in FIG. 12 . The wireless terminal 26(12) thus attempts to againacquire the first type system information, in hopes that the SI messageacquisition process can thereafter be repeated and perhaps in suchrepeat of the SI message acquisition process the requested SI messagewill be obtained. In an example implementation, the wireless terminal26(12) may optionally reacquire MIB prior to reacquisition of SIB 1.Accordingly, not having a valid version of a stored SIB, upon detectionof failure of the SI message acquisition process, the terminal processor40 initiates (re)acquisition of the first type system information.

FIG. 15 shows basic, representative, example acts or steps performed bythe wireless terminal 26(12) of FIG. 12 . Act 15-1 comprises receivingthe first type system information (SI) from the base station apparatus.As mentioned above, the first type system information comprises:availability of a second type SI message, the second type SI messagecomprising at least one system information block (SIB); schedulinginformation for the SI message; an indication of a delivery mode for thesecond type SI message, the delivery mode being either periodicbroadcast or on-demand basis; and, at least one termination conditionfor determination of a failure of an SI message acquisition process forthe on-demand based second type SI message. Act 15-2 comprisestransmitting an SI request message to request at least one second typeSI message indicated as on-demand delivery. Act 15-3 comprisesinitiating the SI message acquisition process. Act 15-4 comprisesdetermining a failure of the SI message acquisition process. Act 15-5comprises, upon a failure of the SI message acquisition process,initiating acquisition of the first type system information

FIG. 16 is a flowchart showing basic, representative, example acts orsteps performed by the access node 22(12) of FIG. 12 . Act 16-1comprises transmitting first type system information (SI). The firsttype SI has been described above. Act 16-2 comprises receiving an SIrequest message to request at least one second type SI message. Act 16-3comprises delivering the requested SI message. As understood from above,the requested SI message may be sent periodically, repeatedlytransmitted at a predetermined interval, for a predetermined length oftime

It was mentioned above that, in one configuration, the wireless terminalmay use a counter, which is incremented at every SI window of aparticular SI message, e.g. SI #k, and that the SI message acquisitionmay end when the requested SI message(s) are successfully received, orwhen the counter reaches a maximum counter value. In someconfigurations, the maximum counter value may be configured by SIB1(e.g. si-MaxAcqAttempts shown in FIG. 13A). FIG. 17A shows the systeminformation acquisition failure detector 80 as comprising such counteras SI window counter 82. Thus in one example implementation of the FIG.12 example embodiment and mode, the termination condition may compriseSI window counter 82 counting up to reach a maximum value, or countingdown from a pre-set value to zero. Such maximum or pre-set value may beconfigured by the radio access node 22(12). The SI window counter 82 isincremented (or decremented) in a case in which the requested SI messagewas not received by the end of one reception opportunity, e.g., a casein which the requested SI message was not received by the end of an SIwindow.

It was further mentioned above that, in another configuration thewireless terminal may start a timer at the beginning of the SI messageacquisition, and that the SI message acquisition may end when therequested SI message(s) are successfully received, or when the timerexpires. In some configuration, the timer is configured by SIB1 (e.g.the timer configuration T #x in FIG. 13B). FIG. 17B shows the systeminformation acquisition failure detector 80 as comprising such a timer:SI message acquisition process timer 84. Thus in another exampleimplementation of the FIG. 12 example embodiment and mode, thetermination condition may comprise SI message acquisition process timer84 expiration of a timer configured by the base station apparatus. TheSI message acquisition process timer 84 is started at the beginning ofthe SI message acquisition process. The timer expiration value may beconfigured by the radio access node 22(12).

As understood from above, the Other SI may comprise one or more (Other)SI messages, also known as second type SI messages. In one exampleimplementation, as reflected by FIG. 18A, the termination condition maybe common for plural, e.g., all, SI messages. That is, in the FIG. 18Aimplementation, the maximum counter value in the case of FIG. 17A, orthe timer value in the case of FIG. 17B, may be common for all SImessages. In this case, the counter value configuration or the timerconfiguration in Minimum SI (e.g., si-MaxAcqAttempts in FIG. 13A, or T#x in FIG. 13B) may comprise a single parameter. Alternatively, as shownin the example implementation of FIG. 18B, the termination condition maybe configured on a per-SI message basis, e.g., uniquely configured forone or more (Other SI) SI messages. In this case, the counter valueconfiguration or the timer configuration in Minimum SI (e.g.si-MaxAcqAttempts in FIG. 13A, or T #x in FIG. 13B) may comprise a listof parameters, each of which configures a corresponding SI message. Ineither the FIG. 18A or FIG. 18B implementations, the terminationcondition(s), whether common or not common, e.g., unique, may bepre-configured or configured by network via system information. Thus,the condition for the wireless terminal to end the SI reception processis referred as a “termination condition” herein.

The foregoing is now discussed in context of a more general 3GPP TS SIacquisition procedure for a UE to acquire the access stratum, AS, andnon-access stratum, NAS, information. This more 3GPP TS procedureapplies to UEs in RRC_IDLE, in RRC_INACTIVE and in RRC_CONNECTED. The UEin RRC_IDLE and RRC_INACTIVE shall ensure having a valid version of (atleast) the MIB, SIB1 as well as SIB X through SIB Y (depending onsupport of the concerned RATs for UE controlled mobility). The UE inRRC_CONNECTED shall ensure having a valid version of (at least) the MIB,SIB1 as well as SIB X (depending on support of mobility towards theconcerned RATs).

For the acquisition of MIB and SIB1, the UE shall perform the acts ofLISTING 1 below (wherein reference to any “section”, “clause”, or“sub-clause” is to the respective section, clause, or sub-clause of 3GPPTS 38.331.)

LISTING 1 1> if the cell is a PSCell: 2> acquire the MIB; 2> perform theactions specified in section 5.2.2.4.1; 1> else: 2> acquire the MIB; 2>if the UE is unable to acquire the MIB;  3> perform the actions asspecified in clause 5.2.2.5; 2> else:  3>   perform the actionsspecified in section 5.2.2.4.1. 2> acquire the SIBI, 2> if the UE isunable to acquire the SIBI:  3> perform the actions as specified inclause 5.2.2.5; 2>  else:  3>perform the actions specified in section5.2.2.4.2.

From the foregoing it is understood that the UE shall apply the SIacquisition procedure as defined above upon cell selection (e.g. uponpower on), cell-reselection, return from out of coverage, afterreconfiguration with sync completion, after entering NR-RAN from anotherRAT, upon receiving an indication that the system information haschanged, upon receiving a PWS notification, upon failing to acquire anSI message; whenever the UE does not have a valid version in the storedSI.

From the foregoing it is understood that, in an example implementation,when acquiring an SI message, the UE may perform the following acts ofListing 2.

LISTING 2    1>  determine the start of the SI-window for the concernedSI message.    1> if SI message acquisition is not triggered due to UErequest:  2> receive DL-SCH using the SI-RNTI from the start of the SI-window and continue until the end of the SI-window whose absolute length in time is given by si-WindowLength, or until the SI message was received;  2> if the SI message was not received by the end of theSI-window,  repeat reception at the next SI-window occasion for theconcerned SI  message;  1> else if SI message acquisition is triggereddue to UE request:   2>Set the SI window counter 82 to 0 (or Start SImessage acquisition process timer 84);   2>[FFS receive DL-SCH using theSI-RNTI from the start of the SI-window and continue until the end ofthe SI-window whose absolute length in time is given by si-WindowLength,or until the SI message was received];   2>[FFS if the SI message wasnot received by the end of the SI-window, increment the SI windowcounter 82 , repeat reception at the next SI-window occasion for theconcerned SI message];   2>if the SI window counter 82 is equal toconfigured maximum value or counted down to zero (or timer SI messageacquisition process timer 84 expires)    3> Initiate the SI acquisitionprocedure. When the UE acquires a MIB or a SIBI or a SI message in acurrently camped/serving cell as described in clause 5.2.2.3, the UEshall store the acquired SI. A version of the SI that the UE stored isout of date after 3 hours. The UE may use such a stored version of theSI e.g. after cell re-selection, upon return from out of coverage orafter the reception of SI change indication. The storage and managementof the stored SI in addition to the SI relevant for the currentcamped/serving cell is left to UE implementation. The UE shall:    1>delete any stored version of a SIB after 3 hours from the moment it wassuccessfully confirmed as valid;    1> if UE has stored version of anySIB:  2>for each SIB:  3> if the stored SIB is area specific SIB and if systemInfoAreaIdentifier and systemInfoValueTag included in the SIBI received from the currently camped/serving cell are identical to the systemInfoAreaIdentifier and systemInfoValueTag associated with stored version of that SIB; or  3> if the stored SIB is cell specific and ifsystemInfoValueTag  included in the SIBI received from the currentlycamped/serving cell is  identical to the systemInfoValueTag associatedwith stored version of that  SIB;  4> consider the stored SIB as validfor the cell;  3> else: 4> (re)acquire the corresponding SI message asspecified in  clause 5.2.2.3.    1> if UE has no stored version of aSIB:  2> (re)acquire the corresponding SI message as specified in clause5.2.2.3.

Unsuccessful Attempted Reception of Broadcasted System Information

The previous embodiments disclose, e.g., procedure(s) for acquiring anSI message currently broadcasted periodically, wherein the wirelessterminal may continue the SI message acquisition until successfulcompletion. This operation may be valid if the concerned SI message isassumed to be broadcasted forever. By the introduction of on-demand SI,however, the assumption is not guaranteed to be true. For instance, whenthe wireless terminal sees deliveryMode=broadcast in SIB1 for the SImessage of concern, it is possible that the access node may betemporarily broadcasting the SI message in response to a request fromanother wireless terminal, and that the access node may stop theperiodic broadcast eventually.

Whereas the example communications system 20(12) of FIG. 12 primarilyconcerns unsuccessful attempted reception of on-demand systeminformation, FIG. 19 shows an example communications system 20(17)comprising wireless terminal 26(17) configured to detect failure of a SIreception process involving a periodically broadcast SI message. Theaccess node 22(17) and wireless terminal 26(17) of FIG. 19 areessentially identical to the respective access node 22 and wirelessterminal 26 of FIG. 2 and FIG. 12 , except as otherwise indicatedherein. In terms of likeness, for example, the radio access node 22(17)comprises node processor 30 and node transceiver circuitry 32, with thenode processor 30 comprising, e.g., node frame/signal scheduler/handler50, system information (SI) generator 54, and node RRC controller 60.Similarly, the wireless terminal 26(17) comprises terminal processor 40,terminal transceiver circuitry 42, with terminal processor 40 comprisingterminal frame/signal scheduler/handler 52, system information (SI)processor 56, and terminal RRC controller 70.

FIG. 19 shows that wireless terminal 26(17) also comprises systeminformation acquisition failure detector 80. As in the case of FIG. 12 ,terminal processor 40, and particularly SI processor 56, may comprise orconstitute the system information acquisition failure detector 80. Thesystem information acquisition failure detector 80 is configured to makea determination of a failure of the SI message acquisition process. Thesystem information acquisition failure detector 80 may make such failuredetermination based on a termination condition, as herein explained.

As in the FIG. 12 example embodiment and mode, system informationgenerator 54 of radio access node 22(12) is configured to generate firsttype system information. For the example embodiment and mode of FIG. 19, and in the example, non-limiting manner shown in FIG. 13 , the firsttype system information comprises (information elements or the likewhich indicate): availability of second type SI messages; schedulinginformation of each of the SI messages; a delivery mode for each of thesecond type SI messages; and, a configuration parameter to configure atleast one termination condition for determination of a failure of an SImessage acquisition process for the on-demand based second type SImessages. As understood herein, a second type SI message comprises atleast one system information block (SIB), and the delivery mode may beeither periodic broadcast or on-demand basis. The transmitter circuitry36 of radio access node 22(17) is configured to transmit the first typesystem information over the radio interface 24 to the wireless terminal26(17), as shown by arrow 19-1 in FIG. 19 .

In the FIG. 19 example embodiment and mode it is assumed that wirelessterminal 26(17) is presently concerned with acquiring a second type SImessage for which the delivery mode is periodic broadcast. As such, theterminal processor 40 is controlling terminal receiver 46 to initiate aSI message acquisition process for a periodically broadcasted secondtype SI message. But it may turn out, however, after initiating the SImessage acquisition process, that the expected periodically broadcastedsecond type SI message(s) are not received. Non-receipt of theperiodically broadcasted second type SI message(s) may be for any ofseveral reasons, including the fact that the broadcast of theperiodically broadcasted second type SI message was at the behest ofanother wireless terminal, with the wireless terminal 26(17) essentiallybeing a third-party beneficiary of the broadcasts, and the access nodehas by now terminated the broadcast of the second type SI messageintended for the another wireless terminal.

Thus, as in the FIG. 12 example embodiment and mode, system informationacquisition failure detector 80 may make a determination of a failure ofthe SI message acquisition process. When so doing, in an exampleembodiment and mode, the terminal processor 40, working in response toor with system information acquisition failure detector 80, isconfigured to initiate acquisition of the first type system information.That is, the terminal processor 40 is configured, upon a failure of theSI message acquisition process involving a periodically broadcastedsecond type SI message, to initiate acquisition of the first type systeminformation, e.g., to again request the first type system information(Minimum SI) from the radio access node 22(17). In FIG. 19 such requestfor first type system information is depicted by arrow 19-4 (there beingno arrow 19-2 or arrow 19-3 in FIG. 19 ).

FIG. 20 is an exemplary message flow diagram of a periodic broadcastbased SI acquisition procedure wherein system information acquisitionfailure is detected. As shown by act 20-0, wireless terminal 26, ineither RRC_IDLE, RRC_INACTIVE or RRC_CONNECTED state stores the contentof SIB #A with the validity information, valueTag=a, si-AreaID=2, whichthe wireless terminal has previously received. From the currentlyserving access node, as act 20-1 the wireless terminal may obtain SIB1as Minimum SI, e.g., first type system information. Obtaining of theSIB1 is also depicted by arrow 19-1 in FIG. 19 . As shown in FIG. 13 ,the SIB1 includes the scheduleInfoList, which in turn may include one ormore schedulingInfo information elements. An example scheduleInfoListfor this scenario is shown in previously-discussed Table 1, wherein thek'th schedulingInfo indicates that the SI message associated with thisschedulingInfo (SI #k, hereafter), containing SIB #A, will be availableby broadcast. Furthermore, the otherSIBInfo corresponding to SIB #Aindicates that the validity information of SIB #A is valueTag=b,si-AreaID=3. It is assumed hereafter that whenever the wireless terminalreceives SIB1, it has already received MIB beforehand. Having receivedthe SIB1 as Minimum SI, e.g., first type system information, thewireless terminal 26(17) knows when the radio access node 22(17) isexpected to broadcast the system information for the sought second typeSI, e.g., SIB #A. As such, the terminal processor 40 of wirelessterminal 26(17) begins the SI message acquisition (represented by act20-3 in FIG. 20 ).

In the SI message acquisition 20-3, the wireless terminal monitorssignals from the access node attempts to obtain the SI messages in thedesignated SI windows derived from the scheduling information(scheduleInfo) in the SIB1, and thereby attempts to receive therequested SI #k. The SI windows are shown by dotted rectangles in FIG.20 . FIG. 20 shows by act 20-3 a, act 20-3 b, and act 20-3 c threesuccessive transmissions of the requested SI #k, all of which areunsuccessful. A tail of a vertical down-pointing arrow in the SI messageacquisition depiction of FIG. 20 is associated with start of the SImessage acquisition, while the head of the same vertical down-pointingarrow is associated with end of the SI message acquisition. In FIG. 20 ,the SI message acquisition 20-3 utterly fails. Failure of the SI messageacquisition is determined by system information acquisition failuredetector 80 which, as indicated above, makes a determination of afailure of the SI message acquisition process based on a terminationcondition. Examples of the termination condition are described herein.

Upon detection of failure of the SI message acquisition process, as act20-4 the terminal processor 40 initiates (re)acquisition of the firsttype system information, e.g., the MINIMAL SI or SIB1, as shown by arrow14-4 in FIG. 14 . The wireless terminal 26(14) thus attempts to againacquire the first type system information, in hopes that the SI messageacquisition process can thereafter be repeated and perhaps in suchrepeat of the SI message acquisition process the requested SI messagewill be obtained. In an example implementation, the wireless terminal26(14) may optionally reacquire MIB prior to reacquisition of SIB 1.Accordingly, not having a valid version of a stored SIB, upon detectionof failure of the SI message acquisition process, the terminal processor40 initiates (re)acquisition of the first type system information.

FIG. 21 is a flowchart showing basic, representative, example acts orsteps performed by the wireless terminal of FIG. 19 . Act 21-1 comprisesreceiving first type system information (SI) from the base stationapparatus. As indicated previously, the first type system informationcomprises: availability of a second type SI message; schedulinginformation for the SI message; an indication of a delivery mode for thesecond type SI message, the delivery mode being either periodicbroadcast or on-demand basis; and, at least one termination conditionfor determination of a failure of an SI message acquisition process. Act21-2 comprises initiating the SI message acquisition process for aperiodically broadcasted second type SI message. Act 21-3 comprisesdetermining a failure of the SI message acquisition process. Act 21-4comprises, upon a failure of the SI message acquisition process,initiating acquisition of the first type system information.

FIG. 22 is a flowchart showing basic, representative, example acts orsteps performed by the access node of FIG. 19 . Act 22-1 comprisestransmitting first type system information (SI) from the base stationapparatus. The first type system information comprises, e.g.,configuration parameters to configure for at least one terminationcondition for determination of a failure of an SI message acquisitionprocess. Act 22-2 comprises broadcasting the periodic broadcast-based SImessages.

As in the FIG. 12 embodiment and mode, wireless terminal 26(17) may usea counter, which is incremented at every SI window of a particular SImessage, e.g. SI #k, and may end the SI message acquisition when therequested SI message(s) are successfully received, or when the counterreaches a maximum counter value. The system information acquisitionfailure detector 80 of FIG. 19 may comprise the aforementioned SI windowcounter 82, shown in FIG. 17A, which may count up to reach a maximumvalue, or count down from a pre-set value to zero. Such maximum orpre-set value may be configured by the radio access node 22(17). The SIwindow counter 82 is incremented (or decremented) in a case in which therequested SI message was not received by the end of one receptionopportunity, e.g., a case in which the requested SI message was notreceived by the end of an SI window.

Also as in the FIG. 12 embodiment and mode, wireless terminal 26(17) maystart a timer at the beginning of the SI message acquisition, and mayend the SI message acquisition when the requested SI message(s) aresuccessfully received, or when the timer expires. The system informationacquisition failure detector 80 of FIG. 19 may comprise theaforementioned SI message acquisition process timer 84 shown in FIG. 17Bwhen the termination condition comprises expiration of acquisitionprocess timer 84. The SI message acquisition process timer 84 is startedat the beginning of the SI message acquisition process. The timerexpiration value may be configured by the radio access node 22(17).

Thus, similar to the example embodiments and modes of FIG. 2 and FIG. 12, for acquisition of periodic broadcast-based SI message(s) as shown inFIG. 19 an extra mechanism to terminate the SI message acquisition mayemployed. In one configuration, the wireless terminal may use a counter,which is incremented at every SI window of a particular SI message (e.g.SI #k). In this configuration, the SI message acquisition triggered byacquiring may end when the requested SI message is successfullyreceived, or when the counter reaches a maximum counter value. (Itshould be understood that this counter implementation is logicallyidentical to an alternative implementation, wherein the counter is setwith the maximum counter value at the beginning of the SI messageacquisition and decremented upon the end of the SI window. In thisimplementation, the SI message acquisition may end when the counterbecomes a pre-determined value, such as zero). In another configurationthe wireless terminal starts a timer at the beginning of the SI messageacquisition. In this configuration, the SI message acquisition may endwhen the requested SI message is successfully received, or when thetimer expires. Similar to the embodiment of FIG. 12 , and as understoodby FIG. 18A and FIG. 18B, the maximum counter value, or the timer value,may be common for all SIB types, per-SIB type basis or per-SI messagebasis, may be pre-configured or configured by network via systeminformation.

It should further be understood that a wireless terminal may beattempting to receive some second type SI by periodic broadcast, and oneor more other second type SI by on-demand delivery. Hence, in a furtherexample embodiment and mode the terminal processor 40 of a wirelessterminal, such as wireless terminal 26(17), may be configured to bothdetect failure of a SI message acquisition process for broadcastedsecond type system information and detect failure of a SI messageacquisition process for on-demand second type system information. Forthis reason the terminal processor 40 of wireless terminal 26(17) showsterminal processor 40 and SI processor 56 in particular as stillcomprising on-demand Other SI request generator 72. Thus it is possiblein some modes for both the process of FIG. 14 and FIG. 19 to beexecuting essentially currently.

When a wireless terminal 26 is capable of both detecting failure of a SImessage acquisition process for broadcasted second type systeminformation and detecting failure of a SI message acquisition processfor on-demand second type system information, the wireless terminal 26may have separate termination conditions for each process. For thatreason the wireless terminal 26 may comprise plural SI window counters82 and/or plural SI message acquisition process timers 84. For example,the wireless terminal may have a first SI window counter 82(B) for a SImessage acquisition process for broadcasted second type systeminformation; and a second SI window counter 82(D) for a SI messageacquisition process for on-demand second type system information. Or,for example, wireless terminal may have a first SI message acquisitionprocess timer 84(B) for a SI message acquisition process for broadcastedsecond type system information; and a second SI message acquisitionprocess timer 84(D) for a SI message acquisition process for on-demandsecond type system information.

Furthermore, the counter configuration or the timer configuration foracquisition of periodic broadcast-based SI message(s) may be configuredvia system information (e.g. SIB1) separately from the configuration foracquisition of on-demand based SI message(s). In this case, SIB1 shownin FIG. 13C with two separate counter configurations(si-MaxAcqAttemptsOnDemand and si-MaxAcqAttemptsPeriodic) or FIG. 13Dwith two separate timer configurations (T #x for on-demand and T #y forperiodic broadcast) may be used. Alternatively, the counter/timerconfiguration common for on-demand and periodic broadcast-based SImessage acquisition may be configured. In this case, SIB1 shown in FIG.13A (common counter configuration) or FIG. 13B (common timerconfiguration) may be used.

The aforementioned more general 3GPP TS SI acquisition procedure for aUE to acquire the AS- and NAS information may be modified in part, e.g.,for acquisition of an SI Message, for the example embodiment and mode ofFIG. 19 as shown below. As indicated earlier, the counters (SI windowcounter 82(B) and SI window counter 82(D)) or the timers (SI messageacquisition process timer 84(B) and SI message acquisition process timer84(D)) may be identical, or alternatively separately configured.

LISTING 3 When acquiring an SI message, the UE shall:  1>determine thestart of the SI-window for the concerned SI message as follows:  1> ifSI message acquisition is not triggered due to UE request:   2> Set thecounter SI window counter 82(B) to 0 (or Start timer SI message  acquisition process timer 84(B));   2>receive DL-SCH using the SI-RNTIfrom the start of the SI-window and continue     until the end of theSI-window whose absolute length in time is given by     si-WindowLength,or until the SI message was received;   2>if the SI message was notreceived by the end of the SI-window, increment the     counter SIwindow counter 82(B), repeat reception at the next SI-window    occasion for the concerned SI message;   2>if the counter SI windowcounter 82(B) is equal to [configured maximum value]     (or timer SImessage acquisition process timer 84(B) expires)    3> Initiate the SIacquisition procedure as defined in sub-clause 5.2.2.3.  1> else if SImessage acquisition is triggered due to UE request:   2> Set the counterSI window counter 82(D) to 0 (or Start timer SI message     acquisitionprocess timer 84(D));   2> [receive DL-SCH using the SI-RNTI from thestart of the SI-window and     continue until the end of the SI-windowwhose absolute length in time is given by     si-WindowLength, or untilthe SI message was received];   2>[if the SI message was not received bythe end of the SI-window, increment the     counter SI window counter82(D) , repeat reception at the next SI-window     occasion for theconcerned SI messagel;   2>if the counter SI window counter 82(D) isequal to [configured maximum value]     (or timer SI message acquisitionprocess timer 84(D) expires)    3> Initiate the SI acquisition procedureas defined in sub-clause 5.2.2.3.

Limiting Duration of System Information Message Acquisition by Number ofModification Periods

FIG. 23 shows an example communications system 20(23) comprisingwireless terminal 26(23) configured to limit duration of systeminformation message acquisition based on a number of modificationperiods. The example embodiment and mode of FIG. 23 may considered to besimilar to previous embodiments and modes which employed a counter, butinstead of counting a number of SI windows, the counter in the exampleembodiment and mode of FIG. 23 essentially counts a number ofmodification periods as a measure for determining when to terminate theSI message acquisition process.

The elements of access node 22(23) and wireless terminal 26(23) of FIG.23 are essentially identical to the corresponding elements respectiveaccess node 22 and wireless terminal 26 of FIG. 2 that have same basereference numbers, except as otherwise indicated herein. In terms oflikeness, for example, the radio access node 22(23) comprises nodeprocessor 30 and node transceiver circuitry 32, with the node processor30 comprising, e.g., node frame/signal scheduler/handler 50, systeminformation (SI) generator 54, and node RRC controller 60. Similarly,the wireless terminal 26(23) comprises terminal processor 40, terminaltransceiver circuitry 42, with terminal processor 40 comprising terminalframe/signal scheduler/handler 52, system information (SI) processor 56,and terminal RRC controller 70.

FIG. 23 also shows that wireless terminal 26(23) comprises systeminformation message acquisition terminator 90. The terminal processor40, and particularly SI processor 56, may comprise or constitute thesystem information message acquisition terminator 90. The SI processor56 performs an SI message acquisition process to acquire the systeminformation transmitted from the network, e.g., from access node 22(23).The system information message acquisition terminator 90 is configuredto terminate the SI message acquisition process after attempting SImessage acquisition for a first number of modification periods. Thus,the system information message acquisition terminator 90 essentiallyserves as and/or comprises a counter for counting up to the first numberof modification periods as criteria for determining when to end the SImessage acquisition process.

A modification period is a preconfigured time duration where the contentof the system information is unchanged. A modification period may bedefined as a time period wherein the system information may betransmitted a number of times with the same content (except somepredefined parameters), as defined by its own scheduling. A modificationperiod can be any predefined time duration established by anypredetermined convention. For example, the modification periods may bethe same or akin to the concept of modification period as defined forLTE in 3GPP TS 36.304, 38.304, 36.331 and/or 38.331, all of which areincorporated herein by reference.

FIG. 24 depicts an example configuration of modification periods. Ineach modification period, defined between two adjacent modificationperiod boundaries, there may be one or more transmission opportunities(e.g., SI windows) allocated for a designated SI message. The accessnode 22(23) may choose to transmit, or not to transmit, the SI messageon these opportunities.

The first number of modification periods may be obtained by anyappropriate manner, and preferably is configured at the wirelessterminal 26(23) by access node 22(23). For example, the node SIgenerator 54 may comprise modification period limit generator 92, whichgenerates the first number of modification periods which is sent to andused by wireless terminal 26(23) for determining when to terminate theSI message acquisition process. For example, FIG. 23 shows by arrow 23-1transmission of an indication of the first number of modificationperiods to wireless terminal 26(23). Alternatively, the first number ofmodification periods may be pre-configured at the wireless terminal26(23), e.g., stored in memory of wireless terminal 26(23) via inputother from the radio access network such as through user interface 48upon programming of wireless terminal 26(23).

In one configuration, transmission of such an SI message, eitherinitiated autonomously by the radio access node or triggered by anon-demand request from a wireless terminal, may be started at the firstboundary of a modification period. Alternatively, in anotherconfiguration, transmission of such an SI message may start at any SIwindow of a modification period. Nonetheless, in either configurationthe SI transmission may end (if the access node decides to end) at thelast SI window of a modification period.

FIG. 25 is a flowchart showing basic, representative, example acts orsteps performed by the wireless terminal of FIG. 23 . Act 25-1 comprisesthe wireless terminal 26(3), e.g., via terminal receiver 46, receivingsystem information (SI) from the radio access node in a SI messageacquisition process. Act 25-2 comprises terminating the SI messageacquisition process after attempting SI message acquisition for a firstnumber of modification periods. As explained herein, a modificationperiod is a preconfigured time duration where the content of the SI isunchanged. The first number of modification periods may be assessed orcounted from a prescribed event, such as a network event or action ofthe wireless terminal. Act 25-2 may be performed by system informationmessage acquisition terminator 90, which may be realized by SI processor56.

FIG. 26 is a flowchart showing basic, representative, example acts orsteps performed by the access node of FIG. 23 . Act 26-1 comprisesconfiguring the wireless terminal with the first number of modificationperiods. Act 26-1 may be performed by modification period limitgenerator 92, and transmission of the first number of modificationperiods from access node 22(23) to wireless terminal 26(23) may be shownby arrow 23-1 in FIG. 23 . Act 26-2 comprises transmitting systeminformation (SI) to the wireless terminal.

The example embodiment and mode of FIG. 27 is a special case of theexample embodiment and mode of FIG. 23 in which the system informationtakes the form of first type system information and second type systeminformation, as previously discussed in conjunction with other exampleembodiments and modes. The elements of access node 22(27) and wirelessterminal 26(27) of FIG. 27 are essentially identical to thecorresponding elements respective access node 22 and wireless terminal26 of FIG. 2 that have same reference numbers, except as otherwiseindicated herein. In terms of likeness, for example, the radio accessnode 22(23) comprises node processor 30 and node transceiver circuitry32, with the node processor 30 comprising, e.g., node frame/signalscheduler/handler 50, system information (SI) generator 54, and node RRCcontroller 60. Similarly, the wireless terminal 26(23) comprisesterminal processor 40, terminal transceiver circuitry 42, with terminalprocessor 40 comprising terminal frame/signal scheduler/handler 52,system information (SI) processor 56, and terminal RRC controller 70.Further, like the example embodiment and mode of FIG. 23 , the wirelessterminal 26(27) of FIG. 27 comprises system information messageacquisition terminator 90 and the access node 22(27) of FIG. 27comprises the modification period limit generator 92. The systeminformation message acquisition terminator 90 of wireless terminal26(27) is likewise configured to terminate the SI message acquisitionprocess after attempting SI message acquisition for a first number ofmodification periods.

The node processor 30 of radio access node 22 includes a systeminformation (SI) generator 54 similar to that of the example embodimentand mode of FIG. 2 wherein at least some of the system informationgenerated and provided by the system information (SI) generator 54 isMinimum System Information (Minimum SI), also known as first type systeminformation, represented by Minimum SI handler 54M. Some of the systeminformation may be Other system information (Other SI), also known assecond type system information, represented by Other SI handler 540 inFIG. 2 . The wireless terminal 26(27) of FIG. 27 may use the systeminformation (SI) generated by radio access node 22(27), and some of theMinimum SI may inform the wireless terminal 26 of the availability ofthe Other IS.

In the example embodiment and mode of FIG. 27 , the terminal receiver 46is configured to receive first type system information (SI) from theradio access node. As understood herein, the first type SI comprises (1)availability of second type SI messages, and (2) an indication of adelivery mode for each of the second type SI messages. The second typeSI message comprises at least one system information block (SIB). Thedelivery mode is either broadcast or on-demand basis. Further, in theexample embodiment and mode of FIG. 27 , like the embodiment and mode ofFIG. 2 , the terminal receiver 46 is configured to transmit an SIrequest message to request at least one second type SI message indicatedas on-demand delivery in a case where the delivery mode of the secondtype SI message is on-demand. Such SI request message is understood withreference to arrow 2-2 of the embodiment and mode of FIG. 2 anddiscussion thereof. In the embodiment and mode of FIG. 27 , themodification period is thus a preconfigured time duration where thecontent of the first type and second type system information isunchanged.

As was mentioned above, the number of modification periods thatconstitutes the first number of modification periods may bepre-configured in the wireless terminal as well as in the access node.Alternatively, the first number of modification periods may beconfigured by the access node via the minimum system information (e.g.SIB1). In the latter case, SI-SchedulingInfo in SIB1, mentioned inearlier example embodiments and modes, may be augmented to comprise aparameter, such as si-NumModBoundaries. The parametersi-NumModBoundaries, may express the first number of modificationperiods, and thereby to instruct the wireless terminal 26(27) regardingthe duration of the SI message acquisition in units of modificationperiod boundaries. This parameter may apply to any cases of the SImessage acquisition (on-demand request or not). If the wireless terminal26(27) is allowed to start the SI message acquisition in the middle of amodification period, in one configuration si-NumModBoundaries mayinclude the modification period where the SI reception is started. Inanother configuration si-NumModBoundaries may include modificationperiods starting at the next modification period boundary. Listing 4A,shown below, illustrates use of a parameter, such assi-NumModBoundaries, to express the first number of modificationperiods.

LISTING 4A -- ASN1START -- TAG-OTHER-SI-INFO-START SI-SchedulingInfo ::=  SEQUENCE {  schedulingInfoList  SEQUENCE (SIZE (1..maxSI-Message)) OFSchedulingInfo,  si-WindowLength  ENUMERATED {ms1, ms2, ms5, ms10, ms15,ms20,       ms40},  si-Request-Config  SI-Request-Config OPTIONAL, --Cond MSG-1  systemInformationAreaID       BIT STRING (SIZE(24)) OPTIONAL, -- First entry is SIB2  sib ValueTagList    SEQUENCE(SIZE (1..maxSIB-1)) OF SIBValueTag,  systemInfoAreaScope   SystemInfoAreaScope OPTIONAL, -- Cond AREA-ID,  si-NumModBoundary    INTEGER (0..7)   OPTIONAL  ... } SchedulingInfo ::= SEQUENCE { si-BroadcastStatus      ENUMERATED {broadcast, onDemand}, si-Periodicity    ENUMERATED {      rf8, rf16, rf32, rf64, rf128,rf256, rf512},  sib-MappingInfo    SIB-Mapping } SIB-Mapping ::=SEQUENCE (SIZE (0..maxSIB-1)) OF SIB-Type SIB-Type ::=    ENUMERATED {     sibType2, sibType3, sibType4, sibType5,      sibType6, sibType7,sibType8, sibType9,      spare8, spare7, spare6, spare5,      spare4,spare3, spare2, spare1,      ...} -- Value TAG per SIB. SIBValueTag ::=INTEGER (0..31)

Listing 4B is an alternative implementation of SI-SchedulingInfo thatconfigures the number of modification period, wherein two parameters,si-NumModBoundariesOnDemand and si-NumModBoundariesPeriodic, mayconfigure the duration of the SI message acquisition. The parameterNumModBoundariesOnDemand may be used in the scenario disclosed in thesecond embodiment, whereas the parameter NumModBoundariesPeriodic may beused in the scenario disclosed in a previous embodiment.

LISTING 4B -- ASN1START -- TAG-OTHER-SI-INFO-START SI-SchedulingInfo ::=  SEQUENCE {  schedulingInfoList SEQUENCE (SIZE (1..maxSI-Message)) OFSchedulingInfo,  si-WindowLength    ENUMERATED {ms1, ms2, ms5, ms10,ms15, ms20,   ms40},  si-Request-Config    SI-Request-Config OPTIONAL,-- Cond MSG-1  systemInformationAreaID    BIT STRING (SIZE (24))  OPTIONAL, -- First entry is SIB2  sib ValueTagList    SEQUENCE (SIZE(1..maxSIB-1)) OF SIBValueTag,  systemInfoAreaScope   SystemInfoAreaScope OPTIONAL, -- Cond AREA-ID,  si-NumModBoundaryPeriodic    INTEGER (0..7) OPTIONAL,  si-NumModBoundaryOnDemand    INTEGER (0..7)  OPTIONAL   ... } SchedulingInfo ::= SEQUENCE {si-BroadcastStatus      ENUMERATED {broadcast, onDemand}, si-Periodicity     ENUMERATED {      rf8, rf16, rf32, rf64, rf128, rf256, rf512},sib-MappingInfo   SIB-Mapping } SIB-Mapping ::= SEQUENCE (SIZE(0..maxSIB-1)) OF SIB-Type SIB-Type ::=    ENUMERATED {       sibType2,sibType3, sibType4, sibType5,       sibType6, sibType7, sibType8,sibType9,  spare8, spare7, spare6, spare5,  spare4, spare3, spare2,spare1,    ...} -- Value TAG per SIB. SIBValueTag ::= INTEGER (0..31)

The procedure of the example embodiments and modes of FIG. 23 and FIG.27 may be akin to Listing 3, except that the counters (N1, N2) arereplaced by si-NumModBoundaries. Alternatively, the counters may bereplaced by si-NumModBoundariesPeriodic and si-NumModBoundariesOnDemandrespectively.

Requiring Wireless Terminal to Wait an Offset Time Before Beginning SiMessage Acquisition

FIG. 28 shows an example communications system 20(28) wherein wirelessterminal 26(28) may be configured, e.g., via the minimum systeminformation (e.g. SIB1), with at least one offset value. The offsetvalue indicates a duration, e.g., of time, that wireless terminal 26(28)is required to wait before starting a SI message acquisition process.

The elements of access node 22(28) and wireless terminal 26(28) of FIG.28 may be essentially identical to the corresponding elements respectiveaccess node 22 and wireless terminal 26 of FIG. 2 that have same basereference numbers, except as otherwise indicated herein. In terms oflikeness, for example, the radio access node 22(28) comprises nodeprocessor 30 and node transceiver circuitry 32, with the node processor30 comprising, e.g., node frame/signal scheduler/handler 50, systeminformation (SI) generator 54, and node RRC controller 60. Similarly,the wireless terminal 26(28) comprises terminal processor 40, terminaltransceiver circuitry 42, with terminal processor 40 comprising terminalframe/signal scheduler/handler 52, system information (SI) processor 56,and terminal RRC controller 70.

In the example embodiment and mode of FIG. 28 , the terminal receiver 46is configured to receive first type system information (SI) from theradio access node. As understood herein, the first type SI comprises (1)availability of second type SI messages, and (2) an indication of adelivery mode for each of the second type SI messages. The second typeSI message comprises at least one system information block (SIB). Thedelivery mode is either broadcast or on-demand basis. Further, in theexample embodiment and mode of FIG. 27 , like the embodiment and mode ofFIG. 2 , the terminal receiver 46 is configured to transmit an SIrequest message to request at least one second type SI message indicatedas on-demand delivery in a case where the delivery mode of the secondtype SI message is on-demand.

FIG. 28 also shows that wireless terminal 26(28) comprises systeminformation acquisition delay controller 94. The terminal processor 40,and particularly SI processor 56, may comprise or constitute the systeminformation acquisition delay controller 94. In the FIG. 28 exampleembodiment and mode, the system information acquisition delay controller94 is configured to require the SI processor 56 to wait, after receivingfrom the radio access node an acknowledgement for the SI requestmessage, for a time duration specified by an offset value, beforeperforming an SI message acquisition process.

FIG. 28 further shows that the access node 22(28) comprises offset valuegenerator 96. The node SI generator 54 of access node 22(28) generatesfirst type system information which is used to configure the wirelessterminal with an offset value OFF. The offset value OFF is used toinstruct the wireless terminal 26(28) to wait, for a time durationspecified by the offset value OFF, after the wireless terminal receivesfrom access node 22(28) an acknowledgement for the SI request message,before the wireless terminal performs an SI message acquisition process.Receipt from access node 22(28) of an acknowledgement for the SI requestmessage is understood to be an acknowledgment of the request messageshown as arrow 2-2 of FIG. 2 . FIG. 28 shows transmission of the offsetvalue OFF as arrow 28-1.

FIG. 29 is a flowchart showing basic, representative, example acts orsteps performed by the wireless terminal wireless terminal 26(28) ofFIG. 28 . Act 29-1 comprises receiving first type system information(SI) from the radio access node. As explained previously, the first typesystem information may comprise availability of second type SI messages.Act 29-2 comprises transmitting, to access node 22(28), an SI requestmessage to request at least one second type SI message indicated ason-demand delivery in a case where the delivery mode of the second typeSI message is on-demand. Act 29-2 may be performed by terminalframe/signal handler 72 in conjunction with terminal transmitter 44, andis understood with reference to message 2-2 of the example embodimentand mode of FIG. 2 . Act 29-3 comprises, after receiving from the radioaccess node an acknowledgement for the SI request message and beforeperforming an SI message acquisition process, waiting for a timeduration specified by an offset value. The wait of act 29-3 may beassessed and controlled by system information acquisition delaycontroller 94. Act 29-4 comprises performing the SI message acquisitionprocess after the wait of the duration established by the offset valueOFF.

FIG. 30 is a flowchart showing basic, representative, example acts orsteps performed by the access node access node 22(28) of FIG. 28 . Act30-1 comprises the access node 22(28) transmitting the first type systeminformation (SI) to the wireless terminal. Act 30-1 may be performed bynode SI generator 54 in conjunction with core node transmitter 34. Act30-2 comprises the access node 22(28) receiving an SI request message torequest at least one second type SI message. The SI request message maybe understood with reference to message 2-2 of FIG. 2 , for example, andmay be received via node receiver 36 and handled by request handler 72.Act 30-3 comprises the access node 22(28) waiting for a time durationspecified by the offset value (OFF). Act 3-4 comprises the access node22(28) starting to transmit the second type SI message. The offset valueOFF may be generated by offset value generator 96 and transmitted fromaccess node 22(28) to wireless terminal 26(28) by core node transmitter34. As explained previously, the offset value OFF serves to instruct thewireless terminal to wait for a time duration specified by an offsetvalue after the wireless terminal receives, from the radio access node,an acknowledgement for the SI request message, before the wirelessterminal performs an SI message acquisition process.

FIG. 31 illustrates the scenario of the example embodiment and mode ofFIG. 28 , where wireless terminal 26(28), after completing the SIrequest procedure 31-2, waits for the specified duration (offset valueOFF) before starting the SI message acquisition procedure 31-3.

In some configurations, the offset value (offset value OFF) may be usedin a case where the access node 22(28) desires to defer the transmissionof an SI message from the reception of an SI request.

In one configuration the offset value may be provided in units of SIwindows. In the SI window unit configuration, the wireless terminal mayskip the specified number of SI windows.

In another configuration, the offset value may be provided in units ofmodification periods, which have been discussed above. In thismodification period offset value embodiment, the wireless terminal maypostpone the SI message acquisition until the specified number ofmodification periods is consumed.

Furthermore, in another configuration, the offset value may be a timeduration specifying the time (e.g. in units of milliseconds). In thistime case, after the successful completion of the SI request procedure,the wireless terminal may wait for the specified time and may start theSI message acquisition from the following SI window.

The offset value may be pre-configured in the wireless terminal 26(28)as well as in the access node 22(28). Alternatively, as explained above,the offset value OFF may be configured by the access node 22(28), e.g.,via the minimum system information (e.g. SIB1).

In the latter case, e.g., configuration of offset value OFF by theaccess node 22(28), Listing 5A, Listing 5B and Listing 5C below showexample formats of SI-SchedulingInfo, with the offset configured by thenumber of SI windows, the number of modification period, and the timeduration, respectively. Listing 5D shows the case where the access nodeis able to choose one of these configurations, e.g., the configurationof the offset value OFF being expressed in terms of number of SIwindows, number of modification periods, or time duration.

The counter values or the timers to limit the duration of a SI messageacquisition, disclosed in a previous embodiment, may be started upon orafter the end of the waiting duration specified by the offset value.

LISTING 5A: -- ASN1START -- TAG-OTHER-SI-INFO-START SI-SchedulingInfo::=   SEQUENCE {  schedulingInfoList SEQUENCE (SIZE (1..maxSI-Message))OF SchedulingInfo,  si-WindowLength   ENUMERATED {ms1, ms2, ms5, ms10,ms15, ms20,    ms40},  si-Request-Config SI-Request-Config OPTIONAL, --Cond MSG-1  systemInformationAreaID   BIT STRING (SIZE (24))  OPTIONAL,-- First entry is SIB2  sibValueTagList SEQUENCE (SIZE (1..maxSIB-1)) OFSIBValueTag,  systemInfoAreaScope   SystemInfoAreaScope OPTIONAL, --Cond AREA-ID,  si-AcqOffset  INTEGER (0..15) OPTIONAL -- Number of SIwindows  ... }

LISTING 5B: -- ASN1START -- TAG-OTHER-SI-INFO-START SI-SchedulingInfo::=  SEQUENCE {  schedulingInfoList SEQUENCE (SIZE (1..maxSI-Message))OF SchedulingInfo,  si-WindowLength  ENUMERATED {ms1, ms2, ms5, ms10,ms15, ms20,   ms40},  si-Request-Config SI-Request-Config OPTIONAL, --Cond MSG-1  systemInformationAreaID  BIT STRING (SIZE (24))  OPTIONAL,-- First entry is SIB2  sibValueTagList SEQUENCE (SIZE (1..maxSIB-1)) OFSIBValueTag,  systemInfoAreaScope  System InfoAreaScope OPTIONAL, --Cond AREA-ID,  si-AcqOffset  INTEGER (0..7) OPTIONAL -- Number ofmodification  periods  ... }

LISTING 5C: -- ASN1START -- TAG-OTHER-SI-INFO-START SI-SchedulingInfo::=   SEQUENCE {  schedulingInfoList SEQUENCE (SIZE (1..maxSI-Message))OF SchedulingInfo,  si-WindowLength   ENUMERATED {ms1, ms2, ms5, ms10,ms15, ms20,    ms40},  si-Request-Config SI-Request-Config OPTIONAL, --Cond MSG-1  systemInformationAreaID   BIT STRING (SIZE (24)) OPTIONAL,-- First entry is SIB2  sibValueTagList SEQUENCE (SIZE (1..maxSIB-1)) OFSIBValueTag,  systemInfoAreaScope   SystemInfoAreaScope OPTIONAL, --Cond AREA-ID,  si-AcqOffset  ENUMERATED {ms1, ms2, ms5, ms10, ms15,ms20,   ms40} OPTIONAL -- time to wait for SI message acquisition  ... }

LISTING 5D: -- ASN1START -- TAG-OTHER-SI-INFO-START SI-SchedulingInfo::=   SEQUENCE {  schedulingInfoList SEQUENCE (SIZE (1..maxSI-Message))OF Schedulinginfo,  si-WindowLength   ENUMERATED {ms1, ms2, ms5, ms10,ms15, ms20,      ms40},  si-Request-Config SI-Request-Config OPTIONAL,-- Cond MSG-1  systemInformationAreaID   BIT STRING (SIZE (24))OPTIONAL, -- First entry is SIB2  sibValueTagList SEQUENCE (SIZE(1..maxSIB-1)) OF SIBValueTag,  systemInfoAreaScope  SystemInfoAreaScope OPTIONAL, -- Cond AREA-ID,  si-AcqOffset  CHOICE {  offset-SiWindow     INTEGER (0..15), -- Number of modification periods  offset-ModPeriod     INTEGER (0..7), -- Number of modification periods  offset-Duration    ENUMERATED {ms1, ms2, ms5, ms10, ms15, ms20,     ms40} - time to wait for SI message acquisition   } OPTIONAL  ... }

Limiting Duration of System Information Message Acquisition by Number ofTransmission Opportunities

FIG. 32 shows an example communications system 20(32) comprisingwireless terminal 26(32) configured to limit duration of systeminformation message acquisition based on a number of transmissionopportunities. The number of transmission opportunities may mean thenumber of transmission opportunities that the access node is schedulingfor transmission of a certain system information (SI) message. Thenumber of transmission opportunities may be expressed in terms of anyappropriate unit or event(s), such as system information windows ormodification periods, for example, and may express the transmissionopportunities with reference to timing of a certain network event oraction of the wireless terminal.

The elements of access node 22(32) and wireless terminal 26(32) of FIG.32 are essentially identical to the corresponding elements respectiveaccess node 22 and wireless terminal 26 of FIG. 2 that have same basereference numbers, except as otherwise indicated herein. In terms oflikeness, for example, the radio access node 22(32) comprises nodeprocessor 30 and node transceiver circuitry 32, with the node processor30 comprising, e.g., node frame/signal scheduler/handler 50, systeminformation (SI) generator 54, and node RRC controller 60. Similarly,the wireless terminal 26(32) comprises terminal processor 40, terminaltransceiver circuitry 42, with terminal processor 40 comprising terminalframe/signal scheduler/handler 52, system information (SI) processor 56,and terminal RRC controller 70.

FIG. 32 also shows that wireless terminal 26(32) comprises systeminformation message acquisition terminator 90(32). The terminalprocessor 40, and particularly SI processor 56, may comprise orconstitute the system information message acquisition terminator 90(32).The SI processor 56 performs an SI message acquisition process toacquire the system information transmitted from the network, e.g., fromaccess node 22(32). The system information message acquisitionterminator 90(32) is configured to terminate the SI message acquisitionprocess after attempting SI message acquisition for a prescribed numberof transmission opportunities. The prescribed number of transmissionopportunities may be in time reference, e.g., occur after, a prescribedevent such as a network event or an action by the wireless terminal26(32). Thus, the system information message acquisition terminator90(32) essentially serves as and/or comprises a counter for counting upto a prescribed number of transmission opportunities as criteria fordetermining when to end the SI message acquisition process.

The number of transmission opportunities may be obtained by anyappropriate manner, and preferably is configured at the wirelessterminal 26(32) by access node 22(32). For example, the node SIgenerator 54 may comprise transmission opportunity generator 92(32),which generates a number of transmission opportunities which is sent toand used by wireless terminal 26(32) for determining when to terminatethe SI message acquisition process. For example, FIG. 32 shows by arrow32-1 transmission of an indication of the transmission opportunitiesnumber of transmission opportunities to wireless terminal 26(32).Alternatively, the number of transmission opportunities may bepre-configured at the wireless terminal 26(32), e.g., stored in memoryof wireless terminal 26(32) via input other from the radio accessnetwork such as through user interface 48 upon programming of wirelessterminal 26(32).

FIG. 33 is a flowchart showing basic, representative, example acts orsteps performed by the wireless terminal of FIG. 32 . Act 33-1 comprisesthe wireless terminal 26(32) e.g., via terminal receiver 46, receivingfirst type system information (SI) from the radio access node in a SImessage acquisition process. Act 33-2 comprises terminating the SImessage acquisition process after attempting the SI message acquisitionfor a prescribed number of transmission opportunities. Act 33-2 may beperformed by system information message acquisition terminator 90(32),which may be realized by SI processor 56.

FIG. 34 is a flowchart showing basic, representative, example acts orsteps performed by the access node of FIG. 32 . Act 34-1 comprisesconfiguring the wireless terminal with a prescribed number oftransmission opportunities for a system information message, the numberof transmission opportunities indicating at least how many transmissionopportunities the radio access node is scheduling to transmit the SImessage. Act 34-1 may be performed by transmission opportunity generator92(32), and transmission of the number of transmission opportunitiesfrom access node 22(32) to wireless terminal 26(32) may be shown byarrow 32-1 in FIG. 32 . Act 34-2 comprises transmitting systeminformation (SI) to the wireless terminal, e.g., for the prescribednumber of transmission opportunities.

The example embodiment and mode of FIG. 35 is a special case of theexample embodiment and mode of FIG. 32 in which the system informationtakes the form of first type system information and second type systeminformation, as previously discussed in conjunction with other exampleembodiments and modes. The elements of access node 22(35) and wirelessterminal 26(35) of FIG. 35 are essentially identical to thecorresponding elements respective access node 22 and wireless terminal26 of FIG. 2 that have same reference numbers, except as otherwiseindicated herein. In terms of likeness, for example, the radio accessnode 22(35) comprises node processor 30 and node transceiver circuitry32, with the node processor 30 comprising, e.g., node frame/signalscheduler/handler 50, system information (SI) generator 54, and node RRCcontroller 60. Similarly, the wireless terminal 26(35) comprisesterminal processor 40, terminal transceiver circuitry 42, with terminalprocessor 40 comprising terminal frame/signal scheduler/handler 52,system information (SI) processor 56, and terminal RRC controller 70.Further, like the example embodiment and mode of FIG. 32 , the wirelessterminal 26(35) of FIG. 35 comprises system information messageacquisition terminator 90(32) and the access node 22(35) of FIG. 35comprises the transmission opportunity generator 92(32). The systeminformation message acquisition terminator 90 of wireless terminal26(35) is likewise configured to terminate the SI message acquisitionprocess after attempting SI message acquisition for a prescribed numberof transmission opportunities.

The node processor 30 of radio access node 22(35) includes a systeminformation (SI) generator 54 similar to that of the example embodimentand mode of FIG. 2 wherein at least some of the system informationgenerated and provided by the system information (SI) generator 54 isMinimum System Information (Minimum SI), also known as first type systeminformation, represented by Minimum SI handler 54M. Some of the systeminformation may be Other system information (Other SI), also known assecond type system information, represented by Other SI handler 540 inFIG. 2 . The wireless terminal 26(35) of FIG. 35 may use the systeminformation (SI) generated by radio access node 22(35), and some of theMinimum SI may inform the wireless terminal 26 of the availability ofthe Other IS.

In the example embodiment and mode of FIG. 35 , the terminal receiver 46is configured to receive first type system information (SI) from theradio access node. As understood herein, for the example embodiment andmode of FIG. 35 the first type SI comprises (1) availability of SImessages, (2) an indication of a delivery mode for each of the SImessages, and (3) the prescribed number of transmission opportunitiesfor the SI messages. Each of the SI messages comprises at least onesecond type system information block (SIB). The delivery mode is eitherbroadcast or on-demand basis. Further, in the example embodiment andmode of FIG. 27 , like the embodiment and mode of FIG. 2 , the terminalreceiver 46 is configured to transmit an SI request message to requestat least one SI message indicated as on-demand delivery in a case wherethe delivery mode of the SI message is on-demand. Such SI requestmessage is understood with reference to arrow 2-2 of the embodiment andmode of FIG. 2 and discussion thereof. Thus, in the embodiment and modeof FIG. 35 , the prescribed number of transmission opportunities for atleast one SI message indicating at least how many transmissionopportunities the radio access node is scheduling to transmit the SImessage from the time of the transmission of the first type SI.

Thus, in the example embodiment and mode of FIG. 35 , in access node22(35) the transmitter circuitry 34 is configured to transmit first typesystem information (SI) for the FIG. 35 embodiment and mode to thewireless terminal. The node receiver circuitry 36 configured to receivean SI request message to request at least one SI message. The nodeprocessor circuitry 30 and transmission opportunity generator 92(32)configures the wireless terminal, e.g., via the first type SI, with theprescribed number of transmission opportunities for at least one SImessage. As explained previously, in the FIG. 35 embodiment and mode theprescribed number of transmission opportunities indicates at least howmany transmission opportunities the radio access node is scheduling totransmit the second type SI message from the time of the transmission ofthe first type system information

In the FIG. 35 example embodiment and mode, the minimum systeminformation may indicate, for each SI message, the number oftransmission opportunities that the access node is scheduling fortransmission. For an SI message that is currently broadcasted, thenumber of transmission opportunities may indicate how many of theprescribed number of transmission opportunities are still remaining atthe time of transmission for the minimum system information. Meanwhile,for an SI message that is NOT currently broadcasted (to be requestedon-demand), the number of transmission opportunities may indicate atleast how many transmission opportunities that the access node will usefor the SI message once it is requested. In one example implementationof the FIG. 35 example embodiment and mode, one transmission opportunitymay be an SI window. In another example implementation of the FIG. 35example embodiment and mode, one transmission opportunity may be amodification period.

FIG. 36A illustrates one exemplary operation scenario of the exampleembodiment and mode of FIG. 35 for the case or example implementation inwhich the transmission opportunities are SI windows. The first SIB1transmission in FIG. 36A indicates that the broadcast status (BS) (e.g.si-BroadcastStatus) of the SI message of concern is onDemand.Furthermore, the SIB1 also indicates that the number of transmissionopportunities (TOs) is 6, meaning that six transmission opportunities(i.e., six SI windows) will be used to transmit the SI message once theSI message is requested. After the wireless terminal sends an SIrequest, the access node 22(35) starts transmitting the SI message onthe six subsequent SI windows. In the scenario of FIG. 36A, the secondSIB1 transmission, occurring after the fourth SI window, indicates tworemaining TOs for the SI message that is being broadcasted(BS=broadcast). After consuming these six TOs, the TO indicated in thethird SIB1 transmission goes back to 6, whereas BS becomes onDemand.

In the scenario of FIG. 36A, after the successful completion of the SIrequest procedure, the wireless terminal 26(35) may perform the SImessage acquisition until it successfully receives the SI message oruntil it consumes the number of SI windows specified by the TO valuereceived in the first SIB 1. Furthermore, the wireless terminal 26(35)may not attempt to receive the second SIB1 transmission (since notrequired to receive it). However, the second SIB1 transmission maypossibly be received by another wireless terminal, which may attempt toreceive the SI message in the next two subsequent SI windows.

In addition, when combined with BS=broadcast, the transmissionopportunities (TOs) in SIB1 may be also used to provide the wirelessterminal 26(35) the maximum SI windows allowed in an SI messageacquisition. For example, as illustrated in FIG. 36B, the wirelessterminal 26(35) may receive the first SIB1 transmission where TO=12 andBS=broadcast. The wireless terminal 26(35), if desired, may start the SImessage acquisition in up to the 12 subsequent SI windows of the SImessage. After consuming all these SI windows without successful SImessage acquisition, the wireless terminal 26(35) may reacquire SIB1, asdisclosed in the previous embodiments. It should be noted that theaccess node 22(35) may choose to continue transmitting the SI messageafter 12 SI windows, as TO in SIB1 in this case is used only in sake ofthe wireless terminal 26(35) to provide the maximum attempts (in unitsof SI windows) before the SIB1 reacquisition.

FIG. 37 is another exemplary scenario where the transmissionopportunities (TOs) are configured in units of modification periods. Thefirst SIB1 transmission in Modification Period N (MP(N)) indicates twoTOs (i.e., two modification periods) will be used for the transmissionof a SI message. In the first modification period a SI request for theSI message is sent from the wireless terminal 26(35), followed by thetransmission of the SI message from access node 22(35) in the subsequentdesignated SI windows, for the duration of two modification periods. Inone configuration, as shown in FIG. 37 , the configured TOs may includethe modification period where the SI request occurs (MP(N)). In thiscase, as shown in FIG. 37 , TO in the SIB1 transmitted in MP(N+1) may bedecremented by one (i.e. TO=1). In another configuration, TO in the SIB1may not include the modification period where the SI request occurs(MP(N)). In this case, TO=2 in MP(N+1), TO=1 in MP(N+2), and the SImessage transmission may continue until the end of MP(N+2).

Listing 6 shows an example format and coding of SIB1 for the exampleembodiment and mode of FIG. 35 , where si-NumTransmissionOpportunitiesprovide the number of TOs disclosed above, in units of SI-windows (oralternatively in units of modification periods).

LISTING 6 -- ASN1START -- TAG-OTHER-SI-INFO-START SI-SchedulingInfo ::=  SEQUENCE {  schedulingInfoList SEQUENCE (SIZE (1..maxSI-Message)) OFSchedulingInfo,  si-WindowLength    ENUMERATED {ms1, ms2, ms5, ms10,ms15, ms20,      ms40},  si-Request-Config   SI-Request-ConfigOPTIONAL, -- Cond MSG-1  systemInformationAreaID    BIT STRING (SIZE(24))  OPTIONAL, -- First entry is SIB2  sib ValueTagList    SEQUENCE(SIZE (1..maxSIB-1)) OF SIBValueTag,  systemInfoAreaScope   SystemInfoAreaScope OPTIONAL, -- Cond AREA-ID,  ... } SchedulingInfo::= SEQUENCE { si-BroadcastStatus  ENUMERATED {broadcast, onDemand},si-Periodicity   ENUMERATED }     rf8, rf16, rf32, rf64, rf128, rf256,rf512}, sib-MappingInfo   SIB-Mapping, si-NumTransmissionOpportunities     INTEGER(0..31) -- number of remaining TOs for this SI message }SIB-Mapping ::= SEQUENCE (SIZE (0..maxSIB-1)) OF SIB-Type SIB-Type ::=   ENUMERATED {     sibType2, sibType3, sibType4, sibType5,    sibType6, sibType7, sibType8, sibType9,     spare8, spare7, spare6,spare5,     spare4, spare3, spare2, spare1,     ... } -- Value TAG perSIB. SIBValueTag ::= INTEGER (0..31)

Acquisition of on-Demand Based System Information in RRC_CONNECTED State

FIG. 38 -FIG. 41 disclose operations and modes for acquisition ofon-demand based system information in RRC_CONNECTED state. In theexample embodiment and mode of FIG. 38 -FIG. 41 , the wireless terminalmay send to the access node a request for on-demand delivery of one ormore SIBs or SI messages, and the wireless terminal may receive therequested SIBs/SI messages via a message, e.g., a RRC message, dedicatedto the wireless terminal, e.g., specific to the wireless terminal.

FIG. 38 shows example communications system 20(38) as comprising accessnode 22(38) and wireless terminal 26(38). The elements of access node22(38) and wireless terminal 26(38) of FIG. 38 are essentially identicalto the corresponding elements respective access node 22 and wirelessterminal 26 of FIG. 2 and other example embodiments that have same basereference numbers, except as otherwise indicated herein.

In terms of likeness, for example, the radio access node 22(38)comprises node processor 30 and node transceiver circuitry 32. The nodetransceiver circuitry 32 comprises node transmitter or node transmittingcircuitry 34 and node receiver or node receiving circuitry 36. Nodeprocessor 30 comprises, e.g., node frame/signal scheduler/handler 50,system information (SI) generator 54(38), and node RRC controller 60. Asdescribed above, at least some of the system information generated andprovided by the system information (SI) generator 54(38) may be MinimumSystem Information (Minimum SI), also known as first type systeminformation, represented by Minimum SI handler 54M. Some of the systeminformation may be Other system information (Other SI), also known assecond type system information, represented by Other SI handler 540 inFIG. 38 .

Also in terms of likeness, wireless terminal 26(38) comprises terminalprocessor 40 and terminal transceiver circuitry 42. The terminaltransceiver circuitry 42 comprises terminal transmitter or terminaltransmitting circuitry 44 and terminal receiver or terminal receivingcircuitry 46. Terminal processor 40 comprises, e.g., terminalframe/signal scheduler/handler 52, system information (SI) processor56(38), and terminal RRC controller 70.

FIG. 38 also shows that system information (SI) processor 56(38) ofwireless terminal 26(38) comprises system information messageacquisition processor 120; system information request generator 122; andsystem information acquisition timer 124. The system information (SI)processor 56(38) may operate in conjunction with information receivedfrom access node 22(38), such as timer configuration information;configuration for Physical Downlink Control Channel (PDCCH) monitoring;Downlink Control Information (DCI) on PDCCH; and information obtainedfrom a Physical Downlink Shared Channel (PDSCH). Accordingly andcorrespondingly FIG. 38 shows wireless terminal 26(38) as comprising amemory or storage location for timer configuration 130; PDCCHconfiguration 132; Downlink Control Information (DCI) 134; and PhysicalDownlink Shared Channel (PDSCH) 136. The terminal processor 40 maycomprise or constitute the aforementioned aspects or units of systeminformation (SI) processor 56(38). Moreover, since at least some andpreferably all of the information comprising timer configuration 130,PDCCH configuration 132, Downlink Control Information (DCI) 134, andPhysical Downlink Shared Channel (PDSCH) 136 is received throughterminal frame/signal scheduler/handler 52, FIG. 38 shows thatfunctionality and structure of system information (SI) processor 56(38)may, in an example embodiment and mode, overlap with terminalframe/signal scheduler/handler 52, as may occur in the case in whichboth terminal frame/signal scheduler/handler 52 and system information(SI) generator 54(38) are realized by terminal processor 40.

In the example embodiment and mode of FIG. 38 access node 22(38) maygenerate information such as timer configuration and PDCCH configurationfor wireless terminal 26(38). Accordingly, FIG. 38 shows systeminformation (SI) generator 54(38) of access node 22(38) as comprisingtimer configuration generator 140 and a configuration for PhysicalDownlink Control Channel (PDCCH) monitoring, e.g., PDCCH configurationgenerator 142. As in the situation with wireless terminal 26(38), thatfunctionality and structure of system information (SI) generator 54(38)may, in an example embodiment and mode, overlap with node frame/signalscheduler/handler 50, as may occur in the case in which both nodeframe/signal scheduler/handler 50 and system information (SI) generator54(38) are realized by node processor 30.

FIG. 39A and FIG. 39B illustrate an exemplary scenario for theembodiment of FIG. 38 . FIG. 39A describes a scenario in which systeminformation is successfully acquired in response to a request messagefrom the wireless terminal 26(38) when wireless terminal 26(38) is inconnected mode; FIG. 39B describes a scenario in which a request messagefrom the wireless terminal 26(38) in connected mode fails to obtainrequested system information.

Act 39A-0 of FIG. 39A shows wireless terminal 26(38) enteredRRC_Connected state. After entering the RRC_CONNECTED state, wirelessterminal 26(38) may receive one or more configuration messages viadedicated signaling(s), as reflected by act 39A-1. The one or moreconfiguration messages, which may be, e.g. RRCReconfigurationmessage(s), may comprise configuration parameter(s) used for requestingand acquiring on-demand SIBs/SI messages. In one example configuration,the configuration parameter(s) may configure a timer, e.g. timer Txyzalso shown as system information acquisition timer 124 in FIG. 38 , witha timer value to be used in the acquisition procedure of requestedSIBs/SI messages in RRC_CONNECTED. Such timer configuration parameter(s)may indicate how long the system information acquisition timer 124 mayrun before it expires, e.g., either count up or count down, and may bestored in timer configuration memory 130. Another configurationparameter that may be obtained in act 39A-1 is a configuration forPhysical Downlink Control Channel (PDCCH) monitoring, which may bestored in PDCCH configuration memory 132. Upon successful receipt of theconfiguration parameter(s) and the RRCReconfiguration message of act39A-1 in particular, as act 39A-2 the wireless terminal 26(38) may senda RRCReconfigurationComplete message to access node 22(38).

In this example scenario of FIG. 39A, the wireless terminal 26(38)desires to acquire SIB #A or the SI message containing SIB #A, since itis assumed in the scenario of FIG. 39A that there is no valid version ofSIB #A stored in the wireless terminal. In view of lack of a validversion of SIB #A, as act 39A-3 wireless terminal 26(38) may transmit aSystemInformationRequest message to the access node 22(38). TheSystemInformationRequest message of act 39A-3 indicates SIB(s) or SImessage(s) that the wireless terminal 26(38) desires to receive. In theparticular case under discussion, the wireless terminal 26(38) desiresto receive SIB #A. Upon transmitting the SystemInformationRequestmessage of act 39A-3, the wireless terminal 26(38) may initiate a SIB/SImessage acquisition procedure 39A-4. In the SIB/SI message acquisitionprocedure 39A-4, which may be performed by system information messageacquisition processor 120 of FIG. 38 , the wireless terminal may startthe timer 124 and attempt to receive the requested SIB(s)/SI message(s).As shown in FIG. 39A, if the wireless terminal 26(38) receives aSystemInformation message such as that depicted by act 39A-5, and if themessage contains the requested SIB(s)/SI message(s), the wirelessterminal 26(38) may consider that the SIB/SI message acquisitionprocedure is successful, and accordingly may stop the timer 124 and endthe SIB/SI message acquisition procedure 39A-4.

Acts 39B-0 through 39B-2 of the scenario of FIG. 39B are similar to acts39A-0 through 39A-2 of the scenario of FIG. 39A. Thereafter the scenarioof FIG. 39B contrasts with the scenario of FIG. 39A. Whereas FIG. 39Ashows a scenario of successful SIB acquisition, FIG. 39B shows ascenario of unsuccessful SIB acquisition. In the scenario of FIG. 39B,there is no valid version of SIB #A stored in the wireless terminal. Inview of lack of a valid version of SIB #A, as act 39B_3 of FIG. 39B, thewireless terminal 26(38) may transmit a SystemInformationRequest messageto access node 22(38). Upon transmitting the SystemInformationRequestmessage of act 39B-3, as in the scenario of FIG. 39A the wirelessterminal 26(38) may initiate a SIB/SI message acquisition procedure,e.g., SIB/SI message acquisition procedure 39A-4 and starts the systeminformation acquisition timer 124 using the timer configurationparameters stored in memory 130. FIG. 39B further shows that, forwhatever reason, the SystemInformationRequest message of act 39B-3either does not reach access node 22(38) or is not handled by accessnode 22(38) to generate the requested system information. As a result,if the timer 124 expires, i.e., the wireless terminal 26(38) concludesthat access node 22(38) has failed to receive or correctly process theSystemInformation message of act 39B-3 comprising the requestedSIB(s)/SI message(s) during the SIB/SI message acquisition procedure39B-4. Consequently, the wireless terminal 26(38) may consider that theSIB/SI message acquisition procedure 39B-4 of FIG. 39B endsunsuccessfully. The wireless terminal 26(38) may re-transmitSystemInformationRequest. For example, the wireless terminal mayre-transmit SystemInformationRequest, e.g., repeat act 39B-3, in a casethat a retransmission for the transmission is indicated.

Thus, the wireless terminal 26(38) of FIG. 38 comprises receivercircuitry, transmitter circuitry, and processor circuitry. The receivercircuitry, such as terminal receiving circuitry 46, is configured toreceive, in a radio resource control (RRC) connected state, one or moreconfiguration messages via dedicated signaling(s), such as themessage(s) of act 39A-1 or 39B-1 of FIG. 39A and FIG. 3940 B. The one ormore configuration messages may comprise a timer configuration for atimer, e.g., stored in timer configuration memory 130, and aconfiguration for Physical Downlink Control Channel (PDCCH) monitoringstored, e.g., in PDCCH configuration memory 132. The transmittercircuitry, such as terminal transmitting circuitry 44, is configured totransmit, in the RRC connected state, a system information (SI) requestmessage to request at least one system information block (SIB). Suchsystem information (SI) request message, such as theSystemInformationRequest message of act 39A-3, may be generated bysystem information request generator 122 of FIG. 38 . The terminalprocessor circuitry, e.g., terminal processor 40, is configured to startthe timer 124 based on the timer configuration and to perform an SIacquisition process such as that indicated by act 39A-4 in FIG. 39A andact 39B-4 in FIG. 39B. In an example embodiment and mode, the SIacquisition process comprises reception of Downlink Control Information(DCI) on PDCCH based on the configuration for PDCCH monitoring, andreception of Physical Downlink Shared Channel (PDSCH) scheduled by usingthe DCI. The SI acquisition process continues until the at least one SIBis successfully received, as reflected by act 39A-5 in FIG. 39A, or thetimer expires, as reflected by act 39B-5 in FIG. 39B.

The access node 22(38) of FIG. 38 comprises transmitter circuitry,receiver circuitry, and processor circuitry. The transmitter circuitry,such as transmitter circuitry 34 of FIG. 38 , is configured to transmit,to a wireless terminal in a radio resource control (RRC) connectedstate, one or more configuration messages via dedicated signaling(s).The one or more configuration messages may comprise (1) a timerconfiguration for a timer, generated by timer configuration generator140, and (2) a configuration for Physical Downlink Control Channel(PDCCH) monitoring generated by PDCCH configuration generator 142. Thereceiver circuitry, receiver circuitry 36 of FIG. 38 , is configured toreceive, in the RRC connected state, a system information (SI) requestmessage to request at least one system information block (SIB). Thesystem information (SI) request message may be processed by requesthandler 72. The processor circuitry, e.g., node processor 30, isconfigured to perform an SI delivery process. The SI delivery processcomprises: (1) transmission of Downlink Control Information (DCI) onPDCCH based on the configuration for PDCCH monitoring, and transmissionof Physical Downlink Shared Channel (PDSCH) scheduled by using the DCI.The timer is configured for the wireless terminal to terminateacquisition of the at least one SIB in a case that the acquisition isunsuccessful In an example implementation the SystemInformationRequestmessage may be mapped to Uplink Shared Channel (UL-SCH). UL-SCH may bemapped to Physical Uplink Shared Channel (PUSCH). Namely, in an exampleembodiment and mode the SystemInformationRequest message may be mappedto UL-SCH, and transmitted by using PUSCH. Additionally oralternatively, the SystemInformationRequest message may be mapped toPUSCH, and transmitted by using the PUSCH. For example, Downlink Controlinformation (DCI) used for scheduling of PUSCH may be defined. Here, theDCI used for scheduling of PUSCH may be transmitted on Physical DownlinkControl Channel (PDCCH).

Upon or after the transmission of the message by using PUSCH, thewireless terminal may start monitoring Physical Downlink Control Channel(PDCCH) that carries DCI used for scheduling of PDSCH. In order for theaccess node to encode a DCI, and in order for the wireless terminal todecode the DCI, in one configuration, Cell Radio Network TemporaryIdentifier (C-RNTI) may be used. In another configuration, SystemInformation RNTI (SI-RNTI) may be used to encode/decode the DCI. In yetanother configuration, another RNTI (e.g. a new RNTI designated/definedfor acquisition of on-demand SIB(s)/SI message(s) in RRC_CONNECTED) maybe used to encode/decode the DCI. Namely, RNTI(s) may be configured,e.g., by the access node, to the wireless terminal for DCI transmission,e.g. the DCI used for scheduling of PDSCH. In one example configuration,how the access node encodes the DCI may be realized by attaching CyclicRedundancy Check parity bits, also referred to simply as CRC, to theDCI, and scrambling the CRC parity bits by RNTI(s). In this exampleconfiguration, the wireless terminal may attempt to decode, e.g., blinddecoding, a received DCI by de-scrambling the attached CRC parity bitsusing RNTI(s) and then computing the validity of the CRC parity bits.Accordingly, the wireless terminal may attempt to decode DCI with CRCscrambled by RNTI(s), i.e., attempt to decode PDCCH for DCI with CRCscrambled by RNTI(s). In other words, the wireless terminal may attemptto decode PDCCH transmission addressed to RNTI(s).

ps described above, RNTI(s) may include C-RNTI, SI-RNTI, and/or the newRNTI. If the DCI is successfully decoded, e.g., a valid CRC, then thewireless terminal may proceed to receiving the time-frequencyresource(s) on Physical Downlink Shared Channel (PDSCH) scheduled by theDCI. The wireless terminal may consider successful decoding of the PDCCHscheduled according to this DCI as a response for the request ofSIB(s)/SI message(s). Namely, after the transmission of theSystemInformationRequest message, the wireless terminal may startmonitoring PDCCH for DCI, e.g., with C-RNTI, SI-RNTI, and/or the newRNTI, used for scheduling of PDSCH.

If the time-frequency resource(s) on PDSCH scheduled by the DCIcomprises the SystemInformation message with the requested SIB(s)/SImessage(s), the wireless terminal may stop monitoring the PDCCH for DCIused for scheduling of PDSCH, as has been illustrated above by FIG. 39A,for example. In this context, “the resource(s)” refers to the timefrequency resource(s) on PDSCH that is/are indicated by a DCI which isdecodable by the wireless terminal 26(38). If the received DCI cannot bedecoded with the aforementioned RNTI, or the resource(s) on PDSCH doesnot have the SystemInformation message with the requested SIB(s)/SImessage(s), the wireless terminal may continue monitoring the PDCCHuntil the timer expires, as has been illustrated above by FIG. 39B, forexample.

In an example embodiment and mode wireless terminal 26(38) may beconfigured by the access node with a PDCCH configuration, e.g., aconfiguration for PDCCH monitoring, e.g., search space configuration,for the DCI disclosed above. The PDCCH configuration information may bestored in PDCCH configuration memory 132 of FIG. 38 . The PDCCHconfiguration may comprise information used for configuring an index ofa Control Resource Set, CORESET, where the wireless terminal attempts todecode PDCCH for the DCI. The PDCCH configuration may compriseinformation indicating monitoring occasion(s) of PDCCH, such as aperiodicity and/or offset(s) (of slot(s) and/or symbol(s)) where thewireless terminal attempts to decode PDCCH for the DCI. The PDCCHconfiguration may comprise information used for a search space, e.g., awireless terminal-specific search space and/or a common search space,where the wireless terminal attempt to decode PDCCH for the DCI.

For example, the wireless terminal may attempt to decode PDCCH for theDCI used for scheduling of PDSCH only in a specific CORESET, e.g.,CORESET with an index “Y” or CORESET “Y”, with C-RNTI, SI-RNTI, and/ornew RNTI. More specifically, the wireless terminal may attempt to decodethe PDCCH for the DCI in a search space with an index “X” in CORESET “Y”with C-RNTI, SI-RNTI, and/or new RNTI. This search space may be a type-0common search space (CSS). Attempting to decode PDCCH may be alsoreferred to monitoring PDCCH candidates.

In one configuration, the search space with index “X” of CORESET “Y” maybe a search space, e.g. a common search space (CSS), commonly used formonitoring SIBs/SI messages other than SIB1. In another configuration,the search space with index “X” of CORESET “Y” may be a search spacespecific to the wireless terminal, e.g. a wireless terminal-specificsearch space, or a UE-specific search space (USS). In eitherconfiguration, the search space may be configured by the PDCCHconfiguration. The PDCCH configuration may be a part of theaforementioned one or more configuration messages. In addition, oralternatively, the PDCCH configuration is configured by broadcastedsystem information, e.g. SIB 1.

It should be understood that the operation and mode for the on-demandbased SIB/SI message acquisition procedure may be RRC state dependent.That is, when in RRC_CONNECTED, the wireless terminal may follow theoperation and mode disclosed in the example embodiment and mode of FIG.38 . Whereas, when in RRC_IDLE or RRC_INACTIVE, the wireless terminalmay perform one or a combination of previously disclosed embodiments.For example, in RRC_IDLE or RRC_INACTIVE, the wireless terminal may senda request for on-demand delivery of SIB(s)/SI message(s) based on theprocedure illustrated in FIG. 9A or FIG. 9B, then attempt to acquire therequested SIB(s)/SI message(s) at SI-windows during the designatednumber of modification periods.

It should be also understood that before sendingSystemInformationRequest message in the RRC_CONNECTED state, thewireless terminal may have to know (1) if the SIB(s)/SI message(s) torequest is(are) available via on-demand by the cell served by the accessnode, and (2) if the wireless terminal does not have a valid version ofthe SIB(s)/SI message(s). In order to do this, the wireless terminal mayneed to possess the minimum system information (e.g. SIB1) of the cell.In one example configuration, RRCReconfiguration shown in FIG. 39A orFIG. 39B may comprise SIB1 with previously disclosed SI-SchedulingInfo.In another example configuration, if the SIB1 received and stored inRRC_IDLE/RRC_INACTIVE is still valid, the wireless terminal may use thestored SIB1. In yet another example configuration, in a case that thewireless terminal was handed over to the current cell from a previouscell, SIB1 to be used in the current cell may have been provided by theprevious cell via the handover command, e.g. RRCReconfiguration. In yetanother example configuration, the wireless terminal may receivebroadcasted SIB1 in RRC_CONNECTED.

FIG. 40 shows an example flow diagram of the on-demand based SIB/SImessage acquisition procedure in RRC_CONNECTED for the wireless terminalof the example embodiment and mode of FIG. 38 . Act 40-0 shows wirelessterminal 26(38) entered the RRC_CONNECTED state. After enteringRRC_CONNECTED state, as act 40-1 the wireless terminal 28(36) mayreceive the one or more configuration messages. Knowing that someSIB(s)/SI message(s) is/are necessary to acquire, the wireless terminal28(36) may then as act 40-2 send a SystemInformationRequest message tothe access node 22(38). As act 40-3 wireless terminal 26(38) may startthe timer Txyz, e.g., system information acquisition timer 124, whichhas been configured by the one or more configuration messages of act40-1. Thereafter as act 40-4 the wireless terminal 26(38) may monitorPDCCH to decode DCI with the aforementioned RNTI. If the wirelessterminal 26(38) determines as act 40-5 that a PDCCH is successfullydecoded, as act 40-6 the wireless terminal 28(36) may receive PDSCHresource(s) scheduled by the decoded DCI. If it is determined as act40-7 that the PDSCH resource(s) contain(s) the requested SIB(s)/SImessage(s), the on-demand based SIB/SI message acquisition process issuccessfully completed as reflected by act 40-8. If it is determined atact 40-5 that the DCI is not successfully decoded, or if it isdetermined as act 40-7 that the PDSCH resource(s) does not contain therequested SIB(s)/SI message(s), as act 40-9 the wireless terminal 28(36)may check if the timer Txyz, e.g., system information acquisition timer124, has expired. If the check of act 40-9 is positive, e.g., if thesystem information acquisition timer 124 has expired, as act 40-10 thewireless terminal 28(36) may consider that the on-demand based SIB/SImessage acquisition process has ended unsuccessfully. Otherwise, thewireless terminal 28(36) may continue monitoring PDCCH.

FIG. 41 shows representative, basic acts or steps performed by theaccess node 22(38) of FIG. 38 in an on-demand based SIB/SI messagedelivery procedure in RRC_CONNECTED. Act 41-0 depicts the access node22(38) entering or being in RRC_CONNECTED state. After access node22(38) has entered RRC_CONNECTED with the wireless terminal, as act 41-2the access node 22(38) may transmit the one or more configurationmessages to the wireless terminal via dedicated signaling(s).Subsequently as act 41-3 access node 22(38) may then receive from thewireless terminal a SystemInformationRequest message which serves torequest on-demand delivery of SIB(s)/SI message(s). As act 41-4 theaccess node may transmit, on PDCCH, DCI encoded with any appropriateencoding such as the aforementioned RNTI. The DCI enables the wirelessterminal 26(38) to locate the resources, e.g., resources of PDSCH, onwhich the access node 22(38) will transmit the requested systeminformation. As act 41-5 access node 22(38) may transmit the requestedSIB(s)/SI message(s) on the resource(s) which was appointed by theencoded DCI in act 41-4. In one example implementation, as act 41-6 theaccess node 22(38) may then end the on-demand based SIB/SI messagedelivery process. In another example implementation, the access node22(38) may repeat act 41-3 and act 41-4 for multiple times.

Features from each of the example embodiments and modes describedherein, including the example embodiments and modes of FIG. 2 , FIG. 23, FIG. 27 , FIG. 28 , FIG. 32 , and FIG. 35 may be combined with oneanother. Further, features of the “Example Embodiments” enumeratedhereinafter may also be used in conjunction with one another.

Certain units and functionalities of node 22, node 22-12, node 22-19,node 22(23), node 22(27), node 22(28), node 22(32), node 22(35), andnode 22(38), wireless terminal 26, wireless terminal 26-14, wirelessterminal 26-19, wireless terminal 22(23), wireless terminal 22(27),wireless terminal 22(28), wireless terminal 22(32), wireless terminal22(35), and wireless terminal 22(38), are, in example embodiments,implemented by electronic machinery, computer, and/or circuitry. Forexample, the node processors 30 and terminal processors 40 of theexample embodiments herein described and/or encompassed may be comprisedby the computer circuitry of FIG. 42 . FIG. 42 shows an example of suchelectronic machinery or circuitry, whether node or terminal, ascomprising one or more processor(s) circuits 190, program instructionmemory 192; other memory 194 (e.g., RAM, cache, etc.); input/outputinterfaces 196; peripheral interfaces 198; support circuits 199; andbusses 200 for communication between the aforementioned units.

The program instruction memory 192 may comprise coded instructionswhich, when executed by the processor(s), perform acts including but notlimited to those described herein. Thus, it is understood that each ofnode processor 30 and terminal processor 40, for example, comprisememory in which non-transient instructions are stored for execution.

The memory 194, or computer-readable medium, may be one or more ofreadily available memory such as random access memory (RAM), read onlymemory (ROM), floppy disk, hard disk, flash memory or any other form ofdigital storage, local or remote, and is preferably of non-volatilenature. The support circuits 199 are coupled to the processors 190 forsupporting the processor in a conventional manner. These circuitsinclude cache, power supplies, clock circuits, input/output circuitryand subsystems, and the like.

Further, it should be understood that, when a processor or processorcircuitry is mentioned in conjunction with any of the preceding exampleembodiments and modes, it should be understood that the device hostingthe processor, whether wireless terminal or access node, may comprise atleast one processor and at least one memory including computer programcode, the memory and the computer program code being configured to,working with the at least one processor, to cause the host device toperform the functions afore-described.

Thus, the technology disclosed herein solves problems in the field oftelecommunications, including problems in telecommunications nodes suchwireless terminals and access nodes, as well as computers/processors andhardware comprising such nodes. System information is of utmostimportance to the operation of telecommunication nodes, so that eachnode can obtain the necessary network information to coordinate andcommunicate with other nodes and to perform its desired functions. Thesystem information is quite extensive and complex, and may bechangeable/updateable due to network and operating conditions, forexample. Efficiently obtaining and using the system information ischallenging, particularly in view of numerous other telecommunicationsfunctions that may be simultaneously on-going based on the systeminformation. The technology disclosed herein solves problem that mayoccur when system information is requested by a wireless terminal inRRC_CONNECTED state. The technology disclosed herein thus avoids wasteof time and undue expenditure of processing resources.

Various example embodiments and modes of the technology disclosed hereinproposes resource efficient methods of distributing system informationby the following examples:

A radio access network which transmits a set of configuration parametersfor termination conditions in order for a wireless terminal to terminateacquisition procedure of on-demand system information messages in caseof unsuccess acquisition.

A wireless terminal configured to reacquire a minimum system informationin the case where the configured termination conditions are met.

The terminal conditions may include a number of modification periodsconsumed during the SI message acquisition.

The minimum system information further configures a waiting time for UEto wait before starting the SI message acquisition.

The minimum system information further indicates remaining number oftransmission opportunities for an SI message.

A wireless terminal in RRC_CONNECTED state may send an on-demand SIrequest to the access node and monitors dedicated signaling for SIacquisition based on the configuration provided by the access node.

A timer may be configured to the wireless terminal to terminate the SIacquisition in a case that the acquisition is unsuccessful.

One or more of the following documents may be pertinent to one or moreaspects of the technology disclosed herein, all such documents beingincorporated herein by reference in their entireties:

R2-1806720 Open issues of the on demand SI Acquirement CATT R2-1806839SI Period Monitoring for On Demand SI Samsung Electronics Co., LtdR2-1806920 Issue of simultaneously trigging multiple RRC proceduresASUSTeK R2-1807073 Reception of on-demand SI Spreadtrum CommunicationsR2-1807099 Details of RRC SI request Ericsson R2-1807161 Remainingissues on the MSG3 based on-demand SI request PANASONIC R&D CenterGermany R2-1807205 Duration of on-demand SI broadcast EricssonR2-1807269 Acquisition of Essential SIBs Lenovo, Motorola MobilityR2-1807319 Further consideration on the RACH resource and SI requestmapping ZTE Corporation R2-1807328 Considerations on Acquisition of anSI Message Sharp Corporation R2-1807371 Remaining issues on on-demand SIIntel Corporation R2-1807615 Details of SI Message Reception afterSuccessful SI Request vivo R2-1807645 RACH resources allocation for Msg1based SI request CATT R2-1807673 Further issues relates to on-demand SIXiaomi Communications R2-1807690 Email discussion_101bis#43_RA resourcesfor MSG1 on demand request Samsung Electronics Co., Ltd R2-1808198Consideration on Indication for On-demand SI Broadcast Huawei, HiSiliconR2-1808433 When to start SI monitoring after SI request LG ElectronicsInc. R2-1808437 Clarification of broadcast indicator in SIB1 LGElectronics Inc. R2-1808438 Acknowledgement for MSG3 based SI requestfrom MAC layer LG Electronics Inc. R2-1809110 Offline Discussion #67 -RA resources for MSG1 on demand request ZTE Corporation

The technology of this application thus encompasses but is not limitedto the following example embodiments, example features, and exampleadvantages: Example Embodiment 1: A wireless terminal A wirelessterminal that communicates over a radio interface with a radio accessnode of a radio access network (RAN), the wireless terminal comprising:receiver circuitry configured to receive, in a radio resource control(RRC) connected state, one or more configuration messages via dedicatedsignaling(s), the one or more configuration messages comprising: a timerconfiguration for a timer, and; a configuration for Physical DownlinkControl Channel (PDCCH) monitoring; transmitter circuitry configured totransmit, in the RRC connected state, a system information (SI) requestmessage to request at least one system information block (SIB);processor circuitry configured to: start the timer based on the timerconfiguration, and; perform an SI acquisition process, wherein; the SIacquisition process comprises: reception of Downlink Control Information(DCI) on PDCCH based on the configuration for PDCCH monitoring, andreception of Physical Downlink Shared Channel (PDSCH) scheduled by usingthe DCI, and; the acquisition process continues until the at least oneSIB is successfully received or the timer expires.

Example Embodiment 2: The wireless terminal of Example Embodiment 1,wherein a Cell Radio Network Temporary Identifier (C-RNTI) is used forscrambling Cyclic Redundancy Check (CRC) parity bits attached to theDCI.

Example Embodiment 3: The wireless terminal of Example Embodiment 1,wherein a System Information RNTI (SI-RNTI) is used for scramblingCyclic Redundancy Check (CRC) parity bits attached to the DCI.

Example Embodiment 4: The wireless terminal of Example Embodiment 1,wherein a RNTI designated for acquisition of the requested at least oneSIB is used for scrambling Cyclic Redundancy Check (CRC) parity bitsattached to the DCI.

Example Embodiment 5: The wireless terminal of Example Embodiment 1,wherein the configuration for PDCCH monitoring comprises an index of aControl Resource Set (CORESET).

Example Embodiment 6: The wireless terminal of Example Embodiment 1,wherein the configuration for PDCCH monitoring comprises monitoringoccasion(s).

Example Embodiment 7: An access node of a radio access network (RAN),the access node comprising: transmitter circuitry configured totransmit, to a wireless terminal in a radio resource control (RRC)connected state, one or more configuration messages via dedicatedsignaling(s), the one or more configuration messages comprising: a timerconfiguration for a timer, and; a configuration for Physical DownlinkControl Channel (PDCCH) monitoring; receiver circuitry configured toreceive, in the RRC connected state, a system information (SI) requestmessage to request at least one system information block (SIB);processor circuitry configured to perform an SI delivery process,wherein; the SI delivery process comprises: transmission of DownlinkControl Information (DCI) on PDCCH based on the configuration for PDCCHmonitoring, and transmission of Physical Downlink Shared Channel (PDSCH)scheduled by using the DCI, and; the timer is configured for thewireless terminal to terminate acquisition of the at least one SIB in acase that the acquisition is unsuccessful.

Example Embodiment 8: The access node of Example Embodiment 7, wherein aCell Radio Network Temporary Identifier (C-RNTI) is used for scramblingCyclic Redundancy Check (CRC) parity bits attached to the DCI.

Example Embodiment 9: The access node of Example Embodiment 7, wherein aSystem Information RNTI (SI-RNTI) is used for scrambling CyclicRedundancy Check (CRC) parity bits attached to the DCI.

Example Embodiment 10: The access node of Example Embodiment 7, whereina RNTI designated for acquisition of the requested at least one SIB isused for scrambling Cyclic Redundancy Check (CRC) parity bits attachedto the DCI.

Example Embodiment 11: The access node of Example Embodiment 7, whereinthe configuration for PDCCH monitoring comprises information used forconfiguring an index of Control Resource Set (CORESET).

Example Embodiment 12: The access node of Example Embodiment 7, whereinthe configuration for PDCCH monitoring comprises monitoring occasion(s).

Example Embodiment 13: A method for a wireless terminal thatcommunicates over a radio interface with a radio access node of a radioaccess network (RAN), comprising: receiving, in a radio resource control(RRC) connected state, one or more configuration messages via dedicatedsignaling(s), the one or more configuration messages comprising: a timerconfiguration for a timer, and; a configuration for Physical DownlinkControl Channel (PDCCH) monitoring; transmitting, in the RRC connectedstate, a system information (SI) request message to request at least onesystem information block (SIB); starting the timer based on the timerconfiguration, and; performing an SI acquisition process, wherein; theSI acquisition process comprises: reception of Downlink ControlInformation (DCI) on PDCCH based on the configuration for PDCCHmonitoring, and reception of Physical Downlink Shared Channel (PDSCH)scheduled by using the DCI, and; the acquisition process continues untilthe at least one SIB is successfully received or the timer expires.

Example Embodiment 14: The method of Example Embodiment 13, wherein aCell Radio Network Temporary Identifier (C-RNTI) is used for scramblingCyclic Redundancy Check (CRC) parity bits attached to the DCI.

Example Embodiment 15: The method of Example Embodiment 13, wherein aSystem Information RNTI (SI-RNTI) is used for scrambling CyclicRedundancy Check (CRC) parity bits attached to the DCI.

Example Embodiment 16: The method of Example Embodiment 13, wherein aRNTI designated for acquisition of the requested at least one SIB isused for scrambling Cyclic Redundancy Check (CRC) parity bits attachedto the DCI.

Example Embodiment 17: The method of Example Embodiment 13, wherein theconfiguration for PDCCH monitoring comprises an index of a ControlResource Set (CORESET).

Example Embodiment 18: The method of Example Embodiment 13, wherein theconfiguration for PDCCH monitoring comprises monitoring occasion(s).

Example Embodiment 19: A method for an access node of a radio accessnetwork (RAN), the method comprising: transmitting, to a wirelessterminal in a radio resource control (RRC) connected state, one or moreconfiguration messages via dedicated signaling(s), the one or moreconfiguration messages comprising: a timer configuration for a timer,and; a configuration for Physical Downlink Control Channel (PDCCH)monitoring; receiving, in the RRC connected state, a system information(SI) request message to request at least one system information block(SIB); performing an SI delivery process, wherein; the SI deliveryprocess comprises transmission of Downlink Control Information (DCI) onPDCCH based on the configuration for PDCCH monitoring, and transmissionof Physical Downlink Shared Channel (PDSCH) scheduled by using the DCI,and; the timer is configured for the wireless terminal to terminateacquisition of the at least one SIB in a case that the acquisition isunsuccessful.

Example Embodiment 20: The method of Example Embodiment 19, wherein aCell Radio Network Temporary Identifier (C-RNTI) is used for scramblingCyclic Redundancy Check (CRC) parity bits attached to the DCI.

Example Embodiment 21: The method of Example Embodiment 19, wherein aSystem Information RNTI (SI-RNTI) is used for scrambling CyclicRedundancy Check (CRC) parity bits attached to the DCI.

Example Embodiment 22: The method of Example Embodiment 19, wherein aRNTI designated for acquisition of the requested at least one SIB isused for scrambling Cyclic Redundancy Check (CRC) parity bits attachedto the DCI.

Example Embodiment 23: The method of Example Embodiment 19, wherein theconfiguration for PDCCH monitoring comprises information used forconfiguring an index of Control Resource Set (CORESET).

Example Embodiment 24: The method of Example Embodiment 19, wherein theconfiguration for PDCCH monitoring comprises monitoring occasion(s).

Although the processes and methods of the disclosed embodiments may bediscussed as being implemented as a software routine, some of the methodsteps that are disclosed therein may be performed in hardware as well asby a processor running software. As such, the embodiments may beimplemented in software as executed upon a computer system, in hardwareas an application specific integrated circuit or other type of hardwareimplementation, or a combination of software and hardware. The softwareroutines of the disclosed embodiments are capable of being executed onany computer operating system, and is capable of being performed usingany CPU architecture. The instructions of such software are stored onnon-transient computer readable media.

The functions of the various elements including functional blocks,including but not limited to those labeled or described as “computer”,“processor” or “controller”, may be provided through the use of hardwaresuch as circuit hardware and/or hardware capable of executing softwarein the form of coded instructions stored on computer readable medium.Thus, such functions and illustrated functional blocks are to beunderstood as being either hardware-implemented and/orcomputer-implemented, and thus machine-implemented.

In terms of hardware implementation, the functional blocks may includeor encompass, without limitation, digital signal processor (DSP)hardware, reduced instruction set processor, hardware (e.g., digital oranalog) circuitry including but not limited to application specificintegrated circuit(s) [ASIC], and/or field programmable gate array(s)(FPGA(s)), and (where appropriate) state machines capable of performingsuch functions.

In terms of computer implementation, a computer is generally understoodto comprise one or more processors or one or more controllers, and theterms computer and processor and controller may be employedinterchangeably herein. When provided by a computer or processor orcontroller, the functions may be provided by a single dedicated computeror processor or controller, by a single shared computer or processor orcontroller, or by a plurality of individual computers or processors orcontrollers, some of which may be shared or distributed. Moreover, useof the term “processor” or “controller” shall also be construed to referto other hardware capable of performing such functions and/or executingsoftware, such as the example hardware recited above.

The functions of the various elements including functional blocks,including but not limited to those labeled or described as “computer”,“processor” or “controller”, may be provided through the use of hardwaresuch as circuit hardware and/or hardware capable of executing softwarein the form of coded instructions stored on computer readable medium.Thus, such functions and illustrated functional blocks are to beunderstood as being either hardware-implemented and/orcomputer-implemented, and thus machine-implemented.

Nodes that communicate using the air interface also have suitable radiocommunications circuitry. Moreover, the technology can additionally beconsidered to be embodied entirely within any form of computer-readablememory, such as solid-state memory, magnetic disk, or optical diskcontaining an appropriate set of computer instructions that would causea processor to carry out the techniques described herein.

It will be appreciated that the technology disclosed herein is directedto solving radio communications-centric issues and is necessarily rootedin computer technology and overcomes problems specifically arising inradio communications. Moreover, in at least one of its aspects thetechnology disclosed herein improves the functioning of the basicfunction of a wireless terminal and/or node itself so that, for example,the wireless terminal and/or node can operate more effectively byprudent use of radio resources.

Although the description above contains many specificities, these shouldnot be construed as limiting the scope of the technology disclosedherein but as merely providing illustrations of some of the presentlypreferred embodiments of the technology disclosed herein. Thus the scopeof the technology disclosed herein should be determined by the appendedclaims and their legal equivalents. Therefore, it will be appreciatedthat the scope of the technology disclosed herein fully encompassesother embodiments which may become obvious to those skilled in the art,and that the scope of the technology disclosed herein is accordingly tobe limited by nothing other than the appended claims, in which referenceto an element in the singular is not intended to mean “one and only one”unless explicitly so stated, but rather “one or more.” All structural,chemical, and functional equivalents to the elements of theabove-described preferred embodiment that are known to those of ordinaryskill in the art are expressly incorporated herein by reference and areintended to be encompassed by the present claims. Moreover, it is notnecessary for a device or method to address each and every problemsought to be solved by the technology disclosed herein, for it to beencompassed by the present claims. Furthermore, no element, component,or method step in the present disclosure is intended to be dedicated tothe public regardless of whether the element, component, or method stepis explicitly recited in the claims. No claim element herein is to beconstrued under the provisions of 35 U.S.C. 112, sixth paragraph, unlessthe element is expressly recited using the phrase “means for.”

SUMMARY

In one example, a wireless terminal that communicates over a radiointerface with a radio access node of a radio access network (RAN), thewireless terminal comprising: receiver circuitry configured to receive,in a radio resource control (RRC) connected state, one or moreconfiguration messages via dedicated signaling(s), the one or moreconfiguration messages comprising: a timer configuration for a timer,and; a configuration for Physical Downlink Control Channel (PDCCH)monitoring; transmitter circuitry configured to transmit, in the RRCconnected state, a system information (SI) request message to request atleast one system information block (SIB); processor circuitry configuredto: start the timer based on the timer configuration, and; perform an SIacquisition process, wherein; the SI acquisition process comprises:reception of Downlink Control Information (DCI) on PDCCH based on theconfiguration for PDCCH monitoring, and reception of Physical DownlinkShared Channel (PDSCH) scheduled by using the DCI, and; the acquisitionprocess continues until the at least one SIB is successfully received orthe timer expires.

In one example, the wireless terminal, wherein a Cell Radio NetworkTemporary Identifier (C-RNTI) is used for scrambling Cyclic RedundancyCheck (CRC) parity bits attached to the DCI.

In one example, the wireless terminal, wherein a System Information RNTI(SI-RNTI) is used for scrambling Cyclic Redundancy Check (CRC) paritybits attached to the DCI.

In one example, the wireless terminal, wherein a RNTI designated foracquisition of the requested at least one SIB is used for scramblingCyclic Redundancy Check (CRC) parity bits attached to the DCI.

In one example, the wireless terminal, wherein the configuration forPDCCH monitoring comprises an index of a Control Resource Set (CORESET).

In one example, the wireless terminal, wherein the configuration forPDCCH monitoring comprises monitoring occasion(s).

In one example, an access node of a radio access network (RAN), theaccess node comprising: transmitter circuitry configured to transmit, toa wireless terminal in a radio resource control (RRC) connected state,one or more configuration messages via dedicated signaling(s), the oneor more configuration messages comprising: a timer configuration for atimer, and; a configuration for Physical Downlink Control Channel(PDCCH) monitoring; receiver circuitry configured to receive, in the RRCconnected state, a system information (SI) request message to request atleast one system information block (SIB); processor circuitry configuredto perform an SI delivery process, wherein; the SI delivery processcomprises: transmission of Downlink Control Information (DCI) on PDCCHbased on the configuration for PDCCH monitoring, and transmission ofPhysical Downlink Shared Channel (PDSCH) scheduled by using the DCI,and; the timer is configured for the wireless terminal to terminateacquisition of the at least one SIB in a case that the acquisition isunsuccessful.

In one example, the access node, wherein a Cell Radio Network TemporaryIdentifier (C-RNTI) is used for scrambling Cyclic Redundancy Check (CRC)parity bits attached to the DCI.

In one example, the access node, wherein a System Information RNTI(SI-RNTI) is used for scrambling Cyclic Redundancy Check (CRC) paritybits attached to the DCI.

In one example, the access node, wherein a RNTI designated foracquisition of the requested at least one SIB is used for scramblingCyclic Redundancy Check (CRC) parity bits attached to the DCI.

In one example, the access node, wherein the configuration for PDCCHmonitoring comprises information used for configuring an index ofControl Resource Set (CORESET).

In one example, the access node, wherein the configuration for PDCCHmonitoring comprises monitoring occasion(s).

In one example, a method for a wireless terminal that communicates overa radio interface with a radio access node of a radio access network(RAN), comprising: receiving, in a radio resource control (RRC)connected state, one or more configuration messages via dedicatedsignaling(s), the one or more configuration messages comprising: a timerconfiguration for a timer, and; a configuration for Physical DownlinkControl Channel (PDCCH) monitoring; transmitting, in the RRC connectedstate, a system information (SI) request message to request at least onesystem information block (SIB); starting the timer based on the timerconfiguration, and; performing an SI acquisition process, wherein; theSI acquisition process comprises: reception of Downlink ControlInformation (DCI) on PDCCH based on the configuration for PDCCHmonitoring, and reception of Physical Downlink Shared Channel (PDSCH)scheduled by using the DCI, and; the acquisition process continues untilthe at least one SIB is successfully received or the timer expires.

In one example, the method, wherein a Cell Radio Network TemporaryIdentifier (C-RNTI) is used for scrambling Cyclic Redundancy Check (CRC)parity bits attached to the DCI.

In one example, the method, wherein a System Information RNTI (SI-RNTI)is used for scrambling Cyclic Redundancy Check (CRC) parity bitsattached to the DCI.

In one example, the method, wherein a RNTI designated for acquisition ofthe requested at least one SIB is used for scrambling Cyclic RedundancyCheck (CRC) parity bits attached to the DCI.

In one example, the method, wherein the configuration for PDCCHmonitoring comprises an index of a Control Resource Set (CORESET).

In one example, the method, wherein the configuration for PDCCHmonitoring comprises monitoring occasion(s).

In one example, a method for an access node of a radio access network(RAN), the method comprising: transmitting, to a wireless terminal in aradio resource control (RRC) connected state, one or more configurationmessages via dedicated signaling(s), the one or more configurationmessages comprising: a timer configuration for a timer, and; aconfiguration for Physical Downlink Control Channel (PDCCH) monitoring;receiving, in the RRC connected state, a system information (SI) requestmessage to request at least one system information block (SIB);performing an SI delivery process, wherein; the SI delivery processcomprises transmission of Downlink Control Information (DCI) on PDCCHbased on the configuration for PDCCH monitoring, and transmission ofPhysical Downlink Shared Channel (PDSCH) scheduled by using the DCI,and; the timer is configured for the wireless terminal to terminateacquisition of the at least one SIB in a case that the acquisition isunsuccessful.

In one example, the method, wherein a Cell Radio Network TemporaryIdentifier (C-RNTI) is used for scrambling Cyclic Redundancy Check (CRC)parity bits attached to the DCI.

In one example, the method, wherein a System Information RNTI (SI-RNTI)is used for scrambling Cyclic Redundancy Check (CRC) parity bitsattached to the DCI.

In one example, the method, wherein a RNTI designated for acquisition ofthe requested at least one SIB is used for scrambling Cyclic RedundancyCheck (CRC) parity bits attached to the DCI.

In one example, the method, wherein the configuration for PDCCHmonitoring comprises information used for configuring an index ofControl Resource Set (CORESET).

In one example, the method, wherein the configuration for PDCCHmonitoring comprises monitoring occasion(s).

What is claimed is:
 1. A wireless terminal that communicates over aradio interface with a radio access node of a radio access network(RAN), the wireless terminal comprising: receiver circuitry configuredto receive, in a radio resource control (RRC) connected state, one ormore configuration messages via dedicated signaling(s), the one or moreconfiguration messages comprising: a timer configuration for a timer,and; a configuration for Physical Downlink Control Channel (PDCCH)monitoring; transmitter circuitry configured to transmit, in the RRCconnected state, a system information (SI) request message to request atleast one system information block (SIB); processor circuitry configuredto: start the timer based on the timer configuration, and; perform an SIacquisition process, wherein; the SI acquisition process comprises:reception of Downlink Control Information (DCI) on PDCCH based on theconfiguration for PDCCH monitoring, and reception of Physical DownlinkShared Channel (PDSCH) scheduled by using the DCI, and; the acquisitionprocess continues until the at least one SIB is successfully received orthe timer expires.
 2. The wireless terminal of claim 1, wherein a CellRadio Network Temporary Identifier (C-RNTI) is used for scramblingCyclic Redundancy Check (CRC) parity bits attached to the DCI.
 3. Thewireless terminal of claim 1, wherein a System Information RNTI(SI-RNTI) is used for scrambling Cyclic Redundancy Check (CRC) paritybits attached to the DCI.
 4. The wireless terminal of claim 1, wherein aRNTI designated for acquisition of the requested at least one SIB isused for scrambling Cyclic Redundancy Check (CRC) parity bits attachedto the DCI.
 5. The wireless terminal of claim 1, wherein theconfiguration for PDCCH monitoring comprises an index of a ControlResource Set (CORESET).
 6. An access node of a radio access network(RAN), the access node comprising: transmitter circuitry configured totransmit, to a wireless terminal in a radio resource control (RRC)connected state, one or more configuration messages via dedicatedsignaling(s), the one or more configuration messages comprising: a timerconfiguration for a timer, and; a configuration for Physical DownlinkControl Channel (PDCCH) monitoring; receiver circuitry configured toreceive, in the RRC connected state, a system information (SI) requestmessage to request at least one system information block (SIB);processor circuitry configured to perform an SI delivery process,wherein; the SI delivery process comprises: transmission of DownlinkControl Information (DCI) on PDCCH based on the configuration for PDCCHmonitoring, and transmission of Physical Downlink Shared Channel (PDSCH)scheduled by using the DCI, and; the timer is configured for thewireless terminal to terminate acquisition of the at least one SIB in acase that the acquisition is unsuccessful.
 7. The access node of claim6, wherein a Cell Radio Network Temporary Identifier (C-RNTI) is usedfor scrambling Cyclic Redundancy Check (CRC) parity bits attached to theDCI.
 8. The access node of claim 6, wherein a System Information RNTI(SI-RNTI) is used for scrambling Cyclic Redundancy Check (CRC) paritybits attached to the DCI.
 9. The access node of claim 6, wherein a RNTIdesignated for acquisition of the requested at least one SIB is used forscrambling Cyclic Redundancy Check (CRC) parity bits attached to theDCI.
 10. The access node of claim 6, wherein the configuration for PDCCHmonitoring comprises information used for configuring an index ofControl Resource Set (CORESET).
 11. A method for a wireless terminalthat communicates over a radio interface with a radio access node of aradio access network (RAN), comprising: receiving, in a radio resourcecontrol (RRC) connected state, one or more configuration messages viadedicated signaling(s), the one or more configuration messagescomprising: a timer configuration for a timer, and; a configuration forPhysical Downlink Control Channel (PDCCH) monitoring; transmitting, inthe RRC connected state, a system information (SI) request message torequest at least one system information block (SIB); starting the timerbased on the timer configuration, and; performing an SI acquisitionprocess, wherein; the SI acquisition process comprises: reception ofDownlink Control Information (DCI) on PDCCH based on the configurationfor PDCCH monitoring, and reception of Physical Downlink Shared Channel(PDSCH) scheduled by using the DCI, and; the acquisition processcontinues until the at least one SIB is successfully received or thetimer expires. 12-20. (canceled)